CMP app: fix combination of -certout and -chainout with equal filename arg

apps/cmp.c

@@ -3435,13 +3435,28 @@ int cmp_main(int argc, char **argv)
                             opt_extracertsout, "extra") < 0)
             goto err;
         if (newcert != NULL && (opt_cmd == CMP_IR || opt_cmd == CMP_CR
-                                || opt_cmd == CMP_KUR || opt_cmd == CMP_P10CR))
-            if (!save_cert_or_delete(newcert, opt_certout, "newly enrolled")
-                || save_free_certs(OSSL_CMP_CTX_get1_newChain(cmp_ctx),
-                                   opt_chainout, "chain") < 0
-                || save_free_certs(OSSL_CMP_CTX_get1_caPubs(cmp_ctx),
-                                   opt_cacertsout, "CA") < 0)
+                                || opt_cmd == CMP_KUR || opt_cmd == CMP_P10CR)) {
+            STACK_OF(X509) *newchain = OSSL_CMP_CTX_get1_newChain(cmp_ctx);
+
+            if (newcert != NULL && newchain != NULL /* NULL is on error only */
+                && opt_certout != NULL && opt_chainout != NULL
+                && strcmp(opt_certout, opt_chainout) == 0) {
+                if (!X509_add_cert(newchain, newcert, X509_ADD_FLAG_PREPEND
+                                   | X509_ADD_FLAG_UP_REF)) {
+                    sk_X509_pop_free(newchain, X509_free);
+                    goto err;
+                }
+                if (!save_free_certs(newchain, opt_chainout, "newly enrolled cert and chain"))
+                    goto err;
+            } else {
+                if (save_free_certs(newchain, opt_chainout, "chain") < 0
+                    || !save_cert_or_delete(newcert, opt_certout, "newly enrolled"))
+                    goto err;
+            }
+            if (save_free_certs(OSSL_CMP_CTX_get1_caPubs(cmp_ctx),
+                                opt_cacertsout, "CA") < 0)
                 goto err;
+        }
         if (!OSSL_CMP_CTX_reinit(cmp_ctx))
             goto err;
     }

doc/man1/openssl-cmp.pod.in

@@ -414,6 +414,12 @@ The file where any newly enrolled certificate should be saved.
 =item B<-chainout> I<filename>
 
 The file where the chain of any newly enrolled certificate should be saved.
+This chain excludes the leaf certificate, i.e., the newly enrolled certificate.
+Also the trust anchor (the root certificate) is not included.
+
+If the B<-certout> option is given, too, with equal I<filename> argument,
+then the file produced contains both outputs concatenated:
+the newly enrolled certificate followed by its chain.
 
 =back
 

doc/man3/OSSL_CMP_CTX_new.pod

@@ -642,6 +642,8 @@ If the callback argument is NULL the function tries building an approximate
 chain as far as possible using the same untrusted certificates from the I<ctx>,
 and if this fails it takes the received extraCerts as fallback.
 The resulting cert chain can be retrieved using OSSL_CMP_CTX_get1_newChain().
+This chain excludes the leaf certificate, i.e., the newly enrolled certificate.
+Also the trust anchor (the root certificate) is not included.
 
 OSSL_CMP_CTX_set_certConf_cb() sets the callback used for evaluating the newly
 enrolled certificate before the library sends, depending on its result,

test/recipes/80-test_cmp_http_data/test_enrollment.csv

@@ -66,7 +66,9 @@ expected,description, -section,val, -cmd,val, -newkey,val,val, -newkeypass,val,
 1,disable_confirm, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, -disable_confirm,, -certout,_RESULT_DIR/test.certout_disable.pem,, -out_trusted,root.crt,,BLANK,,BLANK,,,
 0,disable_confirm with parameter, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, -disable_confirm,abc, -certout,_RESULT_DIR/test.certout_disable1.pem,, -out_trusted,root.crt,,BLANK,,BLANK,,,
 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
-1,use certout (and chainout), -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, ,,, -out_trusted,root.crt,,BLANK,,BLANK,,,,-cert,_RESULT_DIR/test.certout_newkey.pem,-untrusted,_RESULT_DIR/test.chainout.pem
+1,use certout (and chainout)            , -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, ,,, -out_trusted,root.crt,,BLANK,,BLANK,,,,-cert,_RESULT_DIR/test.certout_newkey.pem,-untrusted,_RESULT_DIR/test.chainout.pem
+1,certout and chainout sent to same file, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, ,,, -out_trusted,root.crt,,BLANK,,BLANK,,,,-certout,_RESULT_DIR/test.certout_chainout.pem,,-chainout,_RESULT_DIR/test.certout_chainout.pem
+1,use certout and chainout from same file, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, ,,, -out_trusted,root.crt,,BLANK,,BLANK,,,,-cert,_RESULT_DIR/test.certout_chainout.pem,-untrusted,""""
 0,no certout, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, -certout,"""",, -out_trusted,root.crt,,BLANK,,BLANK,,,
 0,certout missing arg, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, -certout,,, -out_trusted,root.crt,,BLANK,,BLANK,,,
 0,certout is non-existing directory and file, -section,, -cmd,ir, -newkey,new.key,, -newkeypass,pass:,,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,,BLANK,, -certout,idontexist/idontexist,, -out_trusted,root.crt,,BLANK,,BLANK,,,