Reimplement the sigalgs processing code into a new implementation

that will be usable with TLS 1.3 with less eye bleed.
ok jsing@ tb@

1 files changed, 13 insertions, 23 deletions

diff --git a/src/lib/libssl/ssl_srvr.c b/src/lib/libssl/ssl_srvr.c
index af9152d3de..0d82271325 100644
--- a/src/lib/libssl/ssl_srvr.c
+++ b/src/lib/libssl/ssl_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_srvr.c,v 1.51 2018/11/08 22:28:52 jsing Exp $ */
+/* $OpenBSD: ssl_srvr.c,v 1.52 2018/11/09 00:34:55 beck Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -166,6 +166,7 @@
 #include <openssl/x509.h>
 
 #include "bytestring.h"
+#include "ssl_sigalgs.h"
 #include "ssl_tlsext.h"
 
 int
@@ -1545,7 +1546,10 @@ ssl3_send_server_key_exchange(SSL *s)
 
                         /* Send signature algorithm. */
                         if (SSL_USE_SIGALGS(s)) {
-                                if (!tls12_get_hashandsig(&server_kex, pkey, md)) {
+                                uint16_t sigalg;
+                                if ((sigalg = ssl_sigalg_value(pkey, md)) ==
+                                    SIGALG_NONE ||
+                                    !CBB_add_u16(&server_kex, sigalg)) {
                                         /* Should never happen */
                                         al = SSL_AD_INTERNAL_ERROR;
                                         SSLerror(s, ERR_R_INTERNAL_ERROR);
@@ -1629,14 +1633,9 @@ ssl3_send_certificate_request(SSL *s)
                         goto err;
 
                 if (SSL_USE_SIGALGS(s)) {
-                        unsigned char *sigalgs_data;
-                        size_t sigalgs_len;
-
-                        tls12_get_req_sig_algs(s, &sigalgs_data, &sigalgs_len);
-
                         if (!CBB_add_u16_length_prefixed(&cert_request, &sigalgs))
                                 goto err;
-                        if (!CBB_add_bytes(&sigalgs, sigalgs_data, sigalgs_len))
+                        if (!ssl_sigalgs_build(&sigalgs))
                                 goto err;
                 }
 
@@ -2089,8 +2088,7 @@ ssl3_get_cert_verify(SSL *s)
         EVP_PKEY *pkey = NULL;
         X509 *peer = NULL;
         EVP_MD_CTX mctx;
-        uint8_t hash_id, sig_id;
-        int al, ok, sigalg, verify;
+        int al, ok, verify;
         const unsigned char *hdata;
         size_t hdatalen;
         int type = 0;
@@ -2157,24 +2155,16 @@ ssl3_get_cert_verify(SSL *s)
                         goto err;
         } else {
                 if (SSL_USE_SIGALGS(s)) {
-                        if (!CBS_get_u8(&cbs, &hash_id))
-                                goto truncated;
-                        if (!CBS_get_u8(&cbs, &sig_id))
-                                goto truncated;
+                        uint16_t sigalg;
 
-                        if ((md = tls12_get_hash(hash_id)) == NULL) {
+                        if (!CBS_get_u16(&cbs, &sigalg))
+                                goto truncated;
+                        if ((md = ssl_sigalg_md(sigalg)) == NULL) {
                                 SSLerror(s, SSL_R_UNKNOWN_DIGEST);
                                 al = SSL_AD_DECODE_ERROR;
                                 goto f_err;
                         }
-
-                        /* Check key type is consistent with signature. */
-                        if ((sigalg = tls12_get_sigid(pkey)) == -1) {
-                                /* Should never happen */
-                                SSLerror(s, ERR_R_INTERNAL_ERROR);
-                                goto err;
-                        }
-                        if (sigalg != sig_id) {
+                        if (!ssl_sigalg_pkey_check(sigalg, pkey)) {
                                 SSLerror(s, SSL_R_WRONG_SIGNATURE_TYPE);
                                 al = SSL_AD_DECODE_ERROR;
                                 goto f_err;