Multiple fixes for ssl3_digest_cached_records() - if EVP_MD_CTX_create()

fails, the NULL check will add an error but it does not abort. This will
result in EVP_DigestInit_ex() being called with a NULL context.
Also ensure that we check the return values from EVP_DigestInit_ex() and
EVP_DigestUpdate().

ok deraadt@ miod@

1 files changed, 12 insertions, 8 deletions

diff --git a/src/lib/libssl/src/ssl/s3_enc.c b/src/lib/libssl/src/ssl/s3_enc.c
index dbefad77b2..f4ac5222f3 100644
--- a/src/lib/libssl/src/ssl/s3_enc.c
+++ b/src/lib/libssl/src/ssl/s3_enc.c
@@ -584,31 +584,35 @@ ssl3_digest_cached_records(SSL *s)
         long hdatalen;
         void *hdata;
 
-        /* Allocate handshake_dgst array */
         ssl3_free_digest_list(s);
+
         s->s3->handshake_dgst = calloc(SSL_MAX_DIGEST, sizeof(EVP_MD_CTX *));
         hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
         if (hdatalen <= 0) {
-                SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS, SSL_R_BAD_HANDSHAKE_LENGTH);
+                SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS,
+                    SSL_R_BAD_HANDSHAKE_LENGTH);
                 return 0;
         }
 
-        /* Loop through bitso of algorithm2 field and create MD_CTX-es */
+        /* Loop through bits of the algorithm2 field and create MD contexts. */
         for (i = 0; ssl_get_handshake_digest(i, &mask, &md); i++) {
                 if ((mask & ssl_get_algorithm2(s)) && md) {
                         s->s3->handshake_dgst[i] = EVP_MD_CTX_create();
                         if (s->s3->handshake_dgst[i] == NULL) {
                                 SSLerr(SSL_F_SSL3_DIGEST_CACHED_RECORDS,
                                     ERR_R_MALLOC_FAILURE);
+                                return 0;
                         }
-                        EVP_DigestInit_ex(s->s3->handshake_dgst[i], md, NULL);
-                        EVP_DigestUpdate(s->s3->handshake_dgst[i], hdata, hdatalen);
-                } else {
-                        s->s3->handshake_dgst[i] = NULL;
+                        if (!EVP_DigestInit_ex(s->s3->handshake_dgst[i],
+                            md, NULL))
+                                return 0;
+                        if (!EVP_DigestUpdate(s->s3->handshake_dgst[i], hdata,
+                            hdatalen))
+                                return 0;
                 }
         }
+
         if (!(s->s3->flags & TLS1_FLAGS_KEEP_HANDSHAKE)) {
-                /* Free handshake_buffer BIO */
                 BIO_free(s->s3->handshake_buffer);
                 s->s3->handshake_buffer = NULL;
         }