Add -no_alt_chains option to apps to implement the new

X509_V_FLAG_NO_ALT_CHAINS flag. Using this option means that when building
certificate chains, the first chain found will be the one used. Without this
flag, if the first chain found is not trusted then we will keep looking to
see if we can build an alternative chain instead.
Reviewed-by: NDr. Stephen Henson <steve@openssl.org>

apps/apps.c

@@ -2362,6 +2362,8 @@ int args_verify(char ***pargs, int *pargc,
         flags |= X509_V_FLAG_SUITEB_192_LOS;
     else if (!strcmp(arg, "-partial_chain"))
         flags |= X509_V_FLAG_PARTIAL_CHAIN;
+    else if (!strcmp(arg, "-no_alt_chains"))
+        flags |= X509_V_FLAG_NO_ALT_CHAINS;
     else
         return 0;
 

apps/cms.c

@@ -645,6 +645,8 @@ int MAIN(int argc, char **argv)
         BIO_printf(bio_err, "-CAfile file   trusted certificates file\n");
         BIO_printf(bio_err,
                    "-trusted_first use locally trusted certificates first when building trust chain\n");
+        BIO_printf(bio_err,
+                   "-no_alt_chains only ever use the first certificate chain found\n");
         BIO_printf(bio_err,
                    "-crl_check     check revocation status of signer's certificate using CRLs\n");
         BIO_printf(bio_err,

apps/ocsp.c

@@ -537,6 +537,8 @@ int MAIN(int argc, char **argv)
                    "-CAfile file         trusted certificates file\n");
         BIO_printf(bio_err,
                    "-trusted_first       use locally trusted CA's first when building trust chain\n");
+        BIO_printf(bio_err,
+                   "-no_alt_chains       only ever use the first certificate chain found\n");
         BIO_printf(bio_err,
                    "-VAfile file         validator certificates file\n");
         BIO_printf(bio_err,

apps/s_client.c

@@ -320,6 +320,8 @@ static void sc_usage(void)
     BIO_printf(bio_err, " -CAfile arg   - PEM format file of CA's\n");
     BIO_printf(bio_err,
                " -trusted_first - Use local CA's first when building trust chain\n");
+    BIO_printf(bio_err,
+               " -no_alt_chains - only ever use the first certificate chain found\n");
     BIO_printf(bio_err,
                " -reconnect    - Drop and re-make the connection with the same Session-ID\n");
     BIO_printf(bio_err,

apps/s_server.c

@@ -508,6 +508,8 @@ static void sv_usage(void)
     BIO_printf(bio_err, " -CAfile arg   - PEM format file of CA's\n");
     BIO_printf(bio_err,
                " -trusted_first - Use locally trusted CA's first when building trust chain\n");
+    BIO_printf(bio_err,
+               " -no_alt_chains - only ever use the first certificate chain found\n");
     BIO_printf(bio_err,
                " -nocert       - Don't use any certificates (Anon-DH)\n");
     BIO_printf(bio_err,

apps/smime.c

@@ -443,6 +443,8 @@ int MAIN(int argc, char **argv)
         BIO_printf(bio_err, "-CAfile file   trusted certificates file\n");
         BIO_printf(bio_err,
                    "-trusted_first use locally trusted CA's first when building trust chain\n");
+        BIO_printf(bio_err,
+                   "-no_alt_chains only ever use the first certificate chain found\n");
         BIO_printf(bio_err,
                    "-crl_check     check revocation status of signer's certificate using CRLs\n");
         BIO_printf(bio_err,

apps/verify.c

@@ -236,7 +236,7 @@ int MAIN(int argc, char **argv)
  end:
     if (ret == 1) {
         BIO_printf(bio_err,
-                   "usage: verify [-verbose] [-CApath path] [-CAfile file] [-trusted_first] [-purpose purpose] [-crl_check]");
+                   "usage: verify [-verbose] [-CApath path] [-CAfile file] [-trusted_first] [-purpose purpose] [-crl_check] [-no_alt_chains]");
 #ifndef OPENSSL_NO_ENGINE
         BIO_printf(bio_err, " [-engine e]");
 #endif