apps/cmp.c: Improve initialization of ext_ctx structure w.r.t. CSR

Also improve doc how the -reqexts option affects the CSR given with the -csr option.

Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/14181)

1 files changed, 28 insertions, 26 deletions

diff --git a/apps/cmp.c b/apps/cmp.c
index 1dbd1f7339..887ec5d22e 100644
--- a/apps/cmp.c
+++ b/apps/cmp.c
@@ -1601,6 +1601,10 @@ static int setup_protection_ctx(OSSL_CMP_CTX *ctx, ENGINE *engine)
  */
 static int setup_request_ctx(OSSL_CMP_CTX *ctx, ENGINE *engine)
 {
+    X509_REQ *csr = NULL;
+    X509_EXTENSIONS *exts = NULL;
+    X509V3_CTX ext_ctx;
+
     if (opt_subject == NULL
             && opt_csr == NULL && opt_oldcert == NULL && opt_cert == NULL
             && opt_cmd != CMP_RR && opt_cmd != CMP_GENM)
@@ -1648,30 +1652,41 @@ static int setup_request_ctx(OSSL_CMP_CTX *ctx, ENGINE *engine)
         return 0;
     }
 
+    if (opt_csr != NULL) {
+        if (opt_cmd == CMP_GENM) {
+            CMP_warn("-csr option is ignored for genm command");
+        } else {
+            csr = load_csr_autofmt(opt_csr, "PKCS#10 CSR for p10cr");
+            if (csr == NULL)
+                return 0;
+            if (!OSSL_CMP_CTX_set1_p10CSR(ctx, csr)) {
+                X509_REQ_free(csr);
+                goto oom;
+            }
+        }
+    }
     if (opt_reqexts != NULL || opt_policies != NULL) {
-        X509V3_CTX ext_ctx;
-        X509_EXTENSIONS *exts = sk_X509_EXTENSION_new_null();
-
-        if (exts == NULL)
-            return 0;
-        X509V3_set_ctx(&ext_ctx, NULL, NULL, NULL, NULL, 0);
+        if ((exts = sk_X509_EXTENSION_new_null()) == NULL)
+            goto exts_err;
+        X509V3_set_ctx(&ext_ctx, NULL, NULL, csr, NULL, X509V3_CTX_REPLACE);
         X509V3_set_nconf(&ext_ctx, conf);
         if (opt_reqexts != NULL
             && !X509V3_EXT_add_nconf_sk(conf, &ext_ctx, opt_reqexts, &exts)) {
             CMP_err1("cannot load certificate request extension section '%s'",
                      opt_reqexts);
-            sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
-            return 0;
+            goto exts_err;
         }
         if (opt_policies != NULL
             && !X509V3_EXT_add_nconf_sk(conf, &ext_ctx, opt_policies, &exts)) {
             CMP_err1("cannot load policy cert request extension section '%s'",
                      opt_policies);
-            sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
-            return 0;
+            goto exts_err;
         }
         OSSL_CMP_CTX_set0_reqExtensions(ctx, exts);
+        exts = NULL;
     }
+    X509_REQ_free(csr);
+    csr = NULL;
     if (OSSL_CMP_CTX_reqExtensions_have_SAN(ctx) && opt_sans != NULL) {
         CMP_err("cannot have Subject Alternative Names both via -reqexts and via -sans");
         return 0;
@@ -1720,22 +1735,6 @@ static int setup_request_ctx(OSSL_CMP_CTX *ctx, ENGINE *engine)
     if (opt_popo >= OSSL_CRMF_POPO_NONE)
         (void)OSSL_CMP_CTX_set_option(ctx, OSSL_CMP_OPT_POPO_METHOD, opt_popo);
 
-    if (opt_csr != NULL) {
-        if (opt_cmd == CMP_GENM) {
-            CMP_warn("-csr option is ignored for genm command");
-        } else {
-            X509_REQ *csr = load_csr_autofmt(opt_csr, "PKCS#10 CSR for p10cr");
-
-            if (csr == NULL)
-                return 0;
-            if (!OSSL_CMP_CTX_set1_p10CSR(ctx, csr)) {
-                X509_REQ_free(csr);
-                goto oom;
-            }
-            X509_REQ_free(csr);
-        }
-    }
-
     if (opt_oldcert != NULL) {
         if (opt_cmd == CMP_GENM) {
             CMP_warn("-oldcert option is ignored for genm command");
@@ -1762,6 +1761,9 @@ static int setup_request_ctx(OSSL_CMP_CTX *ctx, ENGINE *engine)
 
  oom:
     CMP_err("out of memory");
+ exts_err:
+    sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
+    X509_REQ_free(csr);
     return 0;
 }