1 files changed, 50 insertions, 43 deletions

diff --git a/src/lib/libssl/ssl_clnt.c b/src/lib/libssl/ssl_clnt.c
index c53fbda4ba..fd78a8e8a5 100644
--- a/src/lib/libssl/ssl_clnt.c
+++ b/src/lib/libssl/ssl_clnt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_clnt.c,v 1.30 2018/08/16 17:39:50 jsing Exp $ */
+/* $OpenBSD: ssl_clnt.c,v 1.31 2018/08/17 16:28:21 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -2362,19 +2362,25 @@ err:
 int
 ssl3_send_client_verify(SSL *s)
 {
-        unsigned char   *p;
-        unsigned char    data[MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH];
-        EVP_PKEY        *pkey;
-        EVP_PKEY_CTX    *pctx = NULL;
-        EVP_MD_CTX       mctx;
-        unsigned         u = 0;
-        unsigned long    n;
-        int              j;
+        CBB cbb, cert_verify, cbb_signature;
+        unsigned char data[MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH];
+        unsigned char *signature = NULL;
+        unsigned int signature_len;
+        EVP_PKEY_CTX *pctx = NULL;
+        EVP_PKEY *pkey;
+        EVP_MD_CTX mctx;
+        const EVP_MD *md;
+        long hdatalen;
+        void *hdata;
 
         EVP_MD_CTX_init(&mctx);
 
+        memset(&cbb, 0, sizeof(cbb));
+
         if (S3I(s)->hs.state == SSL3_ST_CW_CERT_VRFY_A) {
-                p = ssl3_handshake_msg_start(s, SSL3_MT_CERTIFICATE_VERIFY);
+                if (!ssl3_handshake_msg_start_cbb(s, &cbb, &cert_verify,
+                    SSL3_MT_CERTIFICATE_VERIFY))
+                        goto err;
 
                 /*
                  * Create context from key and test if sha1 is allowed as
@@ -2388,6 +2394,9 @@ ssl3_send_client_verify(SSL *s)
                 if (EVP_PKEY_CTX_set_signature_md(pctx, EVP_sha1()) <= 0)
                         ERR_clear_error();
 
+                if ((signature = calloc(1, EVP_PKEY_size(pkey))) == NULL)
+                        goto err;
+
                 if (!SSL_USE_SIGALGS(s)) {
                         if (S3I(s)->handshake_buffer) {
                                 if (!tls1_digest_cached_records(s))
@@ -2403,55 +2412,44 @@ ssl3_send_client_verify(SSL *s)
                  * using agreed digest and cached handshake records.
                  */
                 if (SSL_USE_SIGALGS(s)) {
-                        long hdatalen = 0;
-                        void *hdata;
-                        const EVP_MD *md = s->cert->key->digest;
                         hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer,
                             &hdata);
+                        md = s->cert->key->digest;
                         if (hdatalen <= 0 ||
-                            !tls12_get_sigandhash(p, pkey, md)) {
+                            !tls12_get_sigandhash_cbb(&cert_verify, pkey, md)) {
                                 SSLerror(s, ERR_R_INTERNAL_ERROR);
                                 goto err;
                         }
-                        p += 2;
                         if (!EVP_SignInit_ex(&mctx, md, NULL) ||
                             !EVP_SignUpdate(&mctx, hdata, hdatalen) ||
-                            !EVP_SignFinal(&mctx, p + 2, &u, pkey)) {
+                            !EVP_SignFinal(&mctx, signature, &signature_len,
+                                pkey)) {
                                 SSLerror(s, ERR_R_EVP_LIB);
                                 goto err;
                         }
-                        s2n(u, p);
-                        n = u + 4;
                         if (!tls1_digest_cached_records(s))
                                 goto err;
                 } else if (pkey->type == EVP_PKEY_RSA) {
                         if (RSA_sign(NID_md5_sha1, data,
-                            MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, &(p[2]),
-                            &u, pkey->pkey.rsa) <= 0 ) {
+                            MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, signature,
+                            &signature_len, pkey->pkey.rsa) <= 0 ) {
                                 SSLerror(s, ERR_R_RSA_LIB);
                                 goto err;
                         }
-                        s2n(u, p);
-                        n = u + 2;
                 } else if (pkey->type == EVP_PKEY_EC) {
                         if (!ECDSA_sign(pkey->save_type,
-                            &(data[MD5_DIGEST_LENGTH]),
-                            SHA_DIGEST_LENGTH, &(p[2]),
-                            (unsigned int *)&j, pkey->pkey.ec)) {
+                            &data[MD5_DIGEST_LENGTH], SHA_DIGEST_LENGTH,
+                            signature, &signature_len, pkey->pkey.ec)) {
                                 SSLerror(s, ERR_R_ECDSA_LIB);
                                 goto err;
                         }
-                        s2n(j, p);
-                        n = j + 2;
 #ifndef OPENSSL_NO_GOST
                 } else if (pkey->type == NID_id_GostR3410_94 ||
-                           pkey->type == NID_id_GostR3410_2001) {
+                    pkey->type == NID_id_GostR3410_2001) {
                         unsigned char signbuf[128];
-                        long hdatalen = 0;
-                        void *hdata;
-                        const EVP_MD *md;
-                        int nid;
+                        unsigned int u;
                         size_t sigsize;
+                        int nid;
 
                         hdatalen = BIO_get_mem_data(S3I(s)->handshake_buffer, &hdata);
                         if (hdatalen <= 0) {
@@ -2468,38 +2466,47 @@ ssl3_send_client_verify(SSL *s)
                             !EVP_DigestFinal(&mctx, signbuf, &u) ||
                             (EVP_PKEY_CTX_set_signature_md(pctx, md) <= 0) ||
                             (EVP_PKEY_CTX_ctrl(pctx, -1, EVP_PKEY_OP_SIGN,
-                                               EVP_PKEY_CTRL_GOST_SIG_FORMAT,
-                                               GOST_SIG_FORMAT_RS_LE,
-                                               NULL) <= 0) ||
-                            (EVP_PKEY_sign(pctx, &(p[2]), &sigsize,
-                                           signbuf, u) <= 0)) {
+                                EVP_PKEY_CTRL_GOST_SIG_FORMAT,
+                                GOST_SIG_FORMAT_RS_LE, NULL) <= 0) ||
+                            (EVP_PKEY_sign(pctx, signature, &sigsize,
+                                signbuf, u) <= 0)) {
                                 SSLerror(s, ERR_R_EVP_LIB);
                                 goto err;
                         }
+                        if (sigsize > UINT_MAX)
+                                goto err;
+                        signature_len = sigsize;
                         if (!tls1_digest_cached_records(s))
                                 goto err;
-                        j = sigsize;
-                        s2n(j, p);
-                        n = j + 2;
 #endif
                 } else {
                         SSLerror(s, ERR_R_INTERNAL_ERROR);
                         goto err;
                 }
 
-                S3I(s)->hs.state = SSL3_ST_CW_CERT_VRFY_B;
+                if (!CBB_add_u16_length_prefixed(&cert_verify, &cbb_signature))
+                        goto err;
+                if (!CBB_add_bytes(&cbb_signature, signature, signature_len))
+                        goto err;
 
-                ssl3_handshake_msg_finish(s, n);
+                if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+                        goto err;
+
+                S3I(s)->hs.state = SSL3_ST_CW_CERT_VRFY_B;
         }
 
         EVP_MD_CTX_cleanup(&mctx);
         EVP_PKEY_CTX_free(pctx);
+        free(signature);
 
         return (ssl3_handshake_write(s));
 
-err:
+ err:
+        CBB_cleanup(&cbb);
         EVP_MD_CTX_cleanup(&mctx);
         EVP_PKEY_CTX_free(pctx);
+        free(signature);
+
         return (-1);
 }