Add CMP fuzzing to fuzz/cmp.c, including a couple of helpers in crypto/cmp/

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/11386)

crypto/cmp/cmp_client.c

@@ -764,10 +764,17 @@ X509 *OSSL_CMP_exec_RR_ses(OSSL_CMP_CTX *ctx)
         goto end;
 
     rrep = rp->body->value.rp;
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
     if (sk_OSSL_CMP_PKISI_num(rrep->status) != num_RevDetails) {
         CMPerr(0, CMP_R_WRONG_RP_COMPONENT_COUNT);
         goto end;
     }
+#else
+    if (sk_OSSL_CMP_PKISI_num(rrep->status) < 1) {
+        CMPerr(0, CMP_R_WRONG_RP_COMPONENT_COUNT);
+        goto end;
+    }
+#endif
 
     /* evaluate PKIStatus field */
     si = ossl_cmp_revrepcontent_get_pkisi(rrep, rsid);
@@ -822,15 +829,19 @@ X509 *OSSL_CMP_exec_RR_ses(OSSL_CMP_CTX *ctx)
             goto err;
         }
         if (X509_NAME_cmp(issuer, OSSL_CRMF_CERTID_get0_issuer(cid)) != 0) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
             CMPerr(0, CMP_R_WRONG_CERTID_IN_RP);
             result = NULL;
             goto err;
+#endif
         }
         if (ASN1_INTEGER_cmp(serial,
                              OSSL_CRMF_CERTID_get0_serialNumber(cid)) != 0) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
             CMPerr(0, CMP_R_WRONG_SERIAL_IN_RP);
             result = NULL;
             goto err;
+#endif
         }
     }
 

crypto/cmp/cmp_msg.c

@@ -219,8 +219,13 @@ static OSSL_CRMF_MSG *crm_new(OSSL_CMP_CTX *ctx, int bodytype, int rid)
 
     if (rkey == NULL)
         rkey = ctx->pkey; /* default is independent of ctx->oldClCert */
-    if (rkey == NULL
-            || (bodytype == OSSL_CMP_PKIBODY_KUR && refcert == NULL)) {
+    if (rkey == NULL) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+        CMPerr(0, CMP_R_NULL_ARGUMENT);
+        return NULL;
+#endif
+    }
+    if (bodytype == OSSL_CMP_PKIBODY_KUR && refcert == NULL) {
         CMPerr(0, CMP_R_INVALID_ARGS);
         return NULL;
     }

crypto/cmp/cmp_server.c

@@ -492,11 +492,13 @@ OSSL_CMP_MSG *OSSL_CMP_SRV_process_request(OSSL_CMP_SRV_CTX *srv_ctx,
     default:
         /* transactionID should be already initialized */
         if (ctx->transactionID == NULL) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
             CMPerr(0, CMP_R_UNEXPECTED_PKIBODY);
             /* ignore any (extra) error in next two function calls: */
             (void)OSSL_CMP_CTX_set1_transactionID(ctx, hdr->transactionID);
             (void)ossl_cmp_ctx_set1_recipNonce(ctx, hdr->senderNonce);
             goto err;
+#endif
         }
     }
 
@@ -547,6 +549,7 @@ OSSL_CMP_MSG *OSSL_CMP_SRV_process_request(OSSL_CMP_SRV_CTX *srv_ctx,
     default:
         /* TODO possibly support further request message types */
         CMPerr(0, CMP_R_UNEXPECTED_PKIBODY);
+        break;
     }
 
  err:

crypto/cmp/cmp_vfy.c

@@ -700,26 +700,34 @@ int ossl_cmp_msg_check_received(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg,
         /* detect explicitly permitted exceptions for invalid protection */
         if (!OSSL_CMP_validate_msg(ctx, msg)
                 && (cb == NULL || (*cb)(ctx, msg, 1, cb_arg) <= 0)) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
             CMPerr(0, CMP_R_ERROR_VALIDATING_PROTECTION);
             return -1;
+#endif
         }
     } else {
         /* detect explicitly permitted exceptions for missing protection */
         if (cb == NULL || (*cb)(ctx, msg, 0, cb_arg) <= 0) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
             CMPerr(0, CMP_R_MISSING_PROTECTION);
             return -1;
+#endif
         }
     }
 
     /* check CMP version number in header */
     if (ossl_cmp_hdr_get_pvno(OSSL_CMP_MSG_get0_header(msg)) != OSSL_CMP_PVNO) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
         CMPerr(0, CMP_R_UNEXPECTED_PVNO);
         return -1;
+#endif
     }
 
     if ((rcvd_type = ossl_cmp_msg_get_bodytype(msg)) < 0) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
         CMPerr(0, CMP_R_PKIBODY_ERROR);
         return -1;
+#endif
     }
 
     /* compare received transactionID with the expected one in previous msg */
@@ -727,8 +735,10 @@ int ossl_cmp_msg_check_received(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg,
             && (msg->header->transactionID == NULL
                 || ASN1_OCTET_STRING_cmp(ctx->transactionID,
                                          msg->header->transactionID) != 0)) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
         CMPerr(0, CMP_R_TRANSACTIONID_UNMATCHED);
         return -1;
+#endif
     }
 
     /* compare received nonce with the one we sent */
@@ -736,8 +746,10 @@ int ossl_cmp_msg_check_received(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *msg,
             && (msg->header->recipNonce == NULL
                 || ASN1_OCTET_STRING_cmp(ctx->senderNonce,
                                          msg->header->recipNonce) != 0)) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
         CMPerr(0, CMP_R_RECIPNONCE_UNMATCHED);
         return -1;
+#endif
     }
 
     /*
@@ -776,19 +788,27 @@ int ossl_cmp_verify_popo(const OSSL_CMP_MSG *msg, int accept_RAVerified)
         {
             X509_REQ *req = msg->body->value.p10cr;
 
-            if (X509_REQ_verify(req, X509_REQ_get0_pubkey(req)) > 0)
-                return 1;
-            CMPerr(0, CMP_R_REQUEST_NOT_ACCEPTED);
-            return 0;
+            if (X509_REQ_verify(req, X509_REQ_get0_pubkey(req)) <= 0) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+                CMPerr(0, CMP_R_REQUEST_NOT_ACCEPTED);
+                return 0;
+#endif
+            }
         }
+        break;
     case OSSL_CMP_PKIBODY_IR:
     case OSSL_CMP_PKIBODY_CR:
     case OSSL_CMP_PKIBODY_KUR:
-        return OSSL_CRMF_MSGS_verify_popo(msg->body->value.ir,
-                                          OSSL_CMP_CERTREQID,
-                                          accept_RAVerified);
+        if (!OSSL_CRMF_MSGS_verify_popo(msg->body->value.ir, OSSL_CMP_CERTREQID,
+                                        accept_RAVerified)) {
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+            return 0;
+#endif
+        }
+        break;
     default:
         CMPerr(0, CMP_R_PKIBODY_ERROR);
         return 0;
     }
+    return 1;
 }

fuzz/build.info

@@ -11,6 +11,10 @@
 IF[{- !$disabled{"fuzz-afl"} || !$disabled{"fuzz-libfuzzer"} -}]
   PROGRAMS{noinst}=asn1 asn1parse bignum bndiv client conf crl server x509
 
+  IF[{- !$disabled{"cmp"} -}]
+    PROGRAMS{noinst}=cmp
+  ENDIF
+
   IF[{- !$disabled{"cms"} -}]
     PROGRAMS{noinst}=cms
   ENDIF
@@ -39,6 +43,10 @@ IF[{- !$disabled{"fuzz-afl"} || !$disabled{"fuzz-libfuzzer"} -}]
   INCLUDE[client]=../include {- $ex_inc -}
   DEPEND[client]=../libcrypto ../libssl {- $ex_lib -}
 
+  SOURCE[cmp]=cmp.c driver.c
+  INCLUDE[cmp]=../include {- $ex_inc -}
+  DEPEND[cmp]=../libcrypto {- $ex_lib -}
+
   SOURCE[cms]=cms.c driver.c
   INCLUDE[cms]=../include {- $ex_inc -}
   DEPEND[cms]=../libcrypto {- $ex_lib -}
@@ -67,6 +75,10 @@ ENDIF
 IF[{- !$disabled{tests} -}]
   PROGRAMS{noinst}=asn1-test asn1parse-test bignum-test bndiv-test client-test conf-test crl-test server-test x509-test
 
+  IF[{- !$disabled{"cmp"} -}]
+    PROGRAMS{noinst}=cmp-test
+  ENDIF
+
   IF[{- !$disabled{"cms"} -}]
     PROGRAMS{noinst}=cms-test
   ENDIF
@@ -95,6 +107,11 @@ IF[{- !$disabled{tests} -}]
   INCLUDE[client-test]=../include
   DEPEND[client-test]=../libcrypto ../libssl
 
+  SOURCE[cmp-test]=cmp.c test-corpus.c
+  INCLUDE[cmp-test]=../include
+  DEPEND[cmp-test]=../libcrypto.a
+  # referring to static lib allows using non-exported functions
+
   SOURCE[cms-test]=cms.c test-corpus.c
   INCLUDE[cms-test]=../include
   DEPEND[cms-test]=../libcrypto

fuzz/cmp.c

@@ -0,0 +1,203 @@
+/*
+ * Copyright 2007-2020 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+/*
+ * Test CMP DER parsing.
+ */
+
+#include <openssl/bio.h>
+#include <openssl/cmp.h>
+#include "../crypto/cmp/cmp_local.h"
+#include <openssl/err.h>
+#include "fuzzer.h"
+#include "rand.inc"
+
+int FuzzerInitialize(int *argc, char ***argv)
+{
+    OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL);
+    ERR_clear_error();
+    CRYPTO_free_ex_index(0, -1);
+    FuzzerSetRand();
+    return 1;
+}
+
+static int num_responses;
+
+static OSSL_CMP_MSG *transfer_cb(OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *req)
+{
+    if (num_responses++ > 2)
+        return NULL; /* prevent loops due to repeated pollRep */
+    return OSSL_CMP_MSG_dup((OSSL_CMP_MSG *)
+                            OSSL_CMP_CTX_get_transfer_cb_arg(ctx));
+}
+
+static int print_noop(const char *func, const char *file, int line,
+                      OSSL_CMP_severity level, const char *msg)
+{
+    return 1;
+}
+
+static int allow_unprotected(const OSSL_CMP_CTX *ctx, const OSSL_CMP_MSG *rep,
+                             int invalid_protection, int expected_type)
+{
+    return 1;
+}
+
+static void cmp_client_process_response(OSSL_CMP_CTX *ctx, OSSL_CMP_MSG *msg)
+{
+    X509_NAME *name = X509_NAME_new();
+    ASN1_INTEGER *serial = ASN1_INTEGER_new();
+
+    ctx->unprotectedSend = 1; /* satisfy ossl_cmp_msg_protect() */
+    ctx->disableConfirm = 1; /* check just one response message */
+    ctx->popoMethod = OSSL_CRMF_POPO_NONE; /* satisfy ossl_cmp_certReq_new() */
+    ctx->oldCert = X509_new(); /* satisfy crm_new() and ossl_cmp_rr_new() */
+    if (!OSSL_CMP_CTX_set1_secretValue(ctx, (unsigned char *)"",
+                                       0) /* prevent too unspecific error */
+            || ctx->oldCert == NULL
+            || name == NULL || !X509_set_issuer_name(ctx->oldCert, name)
+            || serial == NULL || !X509_set_serialNumber(ctx->oldCert, serial))
+        goto err;
+
+    (void)OSSL_CMP_CTX_set_transfer_cb(ctx, transfer_cb);
+    (void)OSSL_CMP_CTX_set_transfer_cb_arg(ctx, msg);
+    (void)OSSL_CMP_CTX_set_log_cb(ctx, print_noop);
+    num_responses = 0;
+    switch (msg->body != NULL ? msg->body->type : -1) {
+    case OSSL_CMP_PKIBODY_IP:
+        (void)OSSL_CMP_exec_IR_ses(ctx);
+        break;
+    case OSSL_CMP_PKIBODY_CP:
+        (void)OSSL_CMP_exec_CR_ses(ctx);
+        (void)OSSL_CMP_exec_P10CR_ses(ctx);
+        break;
+    case OSSL_CMP_PKIBODY_KUP:
+        (void)OSSL_CMP_exec_KUR_ses(ctx);
+        break;
+    case OSSL_CMP_PKIBODY_POLLREP:
+        ctx->status = OSSL_CMP_PKISTATUS_waiting;
+        (void)OSSL_CMP_try_certreq(ctx, OSSL_CMP_PKIBODY_CR, NULL);
+        break;
+    case OSSL_CMP_PKIBODY_RP:
+        (void)OSSL_CMP_exec_RR_ses(ctx);
+        break;
+    case OSSL_CMP_PKIBODY_GENP:
+        sk_OSSL_CMP_ITAV_pop_free(OSSL_CMP_exec_GENM_ses(ctx),
+                                  OSSL_CMP_ITAV_free);
+        break;
+    default:
+        (void)ossl_cmp_msg_check_received(ctx, msg, allow_unprotected, 0);
+        break;
+    }
+ err:
+    X509_NAME_free(name);
+    ASN1_INTEGER_free(serial);
+}
+
+static OSSL_CMP_PKISI *process_cert_request(OSSL_CMP_SRV_CTX *srv_ctx,
+                                            const OSSL_CMP_MSG *cert_req,
+                                            int certReqId,
+                                            const OSSL_CRMF_MSG *crm,
+                                            const X509_REQ *p10cr,
+                                            X509 **certOut,
+                                            STACK_OF(X509) **chainOut,
+                                            STACK_OF(X509) **caPubs)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+    return NULL;
+}
+
+static OSSL_CMP_PKISI *process_rr(OSSL_CMP_SRV_CTX *srv_ctx,
+                                  const OSSL_CMP_MSG *rr,
+                                  const X509_NAME *issuer,
+                                  const ASN1_INTEGER *serial)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+    return NULL;
+}
+
+static int process_genm(OSSL_CMP_SRV_CTX *srv_ctx,
+                        const OSSL_CMP_MSG *genm,
+                        const STACK_OF(OSSL_CMP_ITAV) *in,
+                        STACK_OF(OSSL_CMP_ITAV) **out)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+    return 0;
+}
+
+static void process_error(OSSL_CMP_SRV_CTX *srv_ctx, const OSSL_CMP_MSG *error,
+                          const OSSL_CMP_PKISI *statusInfo,
+                          const ASN1_INTEGER *errorCode,
+                          const OSSL_CMP_PKIFREETEXT *errorDetails)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+}
+
+static int process_certConf(OSSL_CMP_SRV_CTX *srv_ctx,
+                            const OSSL_CMP_MSG *certConf, int certReqId,
+                            const ASN1_OCTET_STRING *certHash,
+                            const OSSL_CMP_PKISI *si)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+    return 0;
+}
+
+static int process_pollReq(OSSL_CMP_SRV_CTX *srv_ctx,
+                           const OSSL_CMP_MSG *pollReq, int certReqId,
+                           OSSL_CMP_MSG **certReq, int64_t *check_after)
+{
+    CMPerr(0, CMP_R_ERROR_PROCESSING_MESSAGE);
+    return 0;
+}
+
+int FuzzerTestOneInput(const uint8_t *buf, size_t len)
+{
+    OSSL_CMP_MSG *msg;
+    BIO *in;
+
+    if (len == 0)
+        return 0;
+
+    in = BIO_new(BIO_s_mem());
+    OPENSSL_assert((size_t)BIO_write(in, buf, len) == len);
+    msg = d2i_OSSL_CMP_MSG_bio(in, NULL);
+    if (msg != NULL) {
+        BIO *out = BIO_new(BIO_s_null());
+        OSSL_CMP_SRV_CTX *srv_ctx = OSSL_CMP_SRV_CTX_new();
+        OSSL_CMP_CTX *client_ctx = OSSL_CMP_CTX_new();
+
+        i2d_OSSL_CMP_MSG_bio(out, msg);
+        ASN1_item_print(out, (ASN1_VALUE *)msg, 4,
+                        ASN1_ITEM_rptr(OSSL_CMP_MSG), NULL);
+        BIO_free(out);
+
+        if (client_ctx != NULL)
+            cmp_client_process_response(client_ctx, msg);
+        if (srv_ctx != NULL
+            && OSSL_CMP_CTX_set_log_cb(OSSL_CMP_SRV_CTX_get0_cmp_ctx(srv_ctx),
+                                       print_noop)
+            && OSSL_CMP_SRV_CTX_init(srv_ctx, NULL, process_cert_request,
+                                     process_rr, process_genm, process_error,
+                                     process_certConf, process_pollReq))
+            OSSL_CMP_MSG_free(OSSL_CMP_SRV_process_request(srv_ctx, msg));
+
+        OSSL_CMP_CTX_free(client_ctx);
+        OSSL_CMP_SRV_CTX_free(srv_ctx);
+        OSSL_CMP_MSG_free(msg);
+    }
+
+    BIO_free(in);
+    ERR_clear_error();
+
+    return 0;
+}
+
+void FuzzerCleanup(void)
+{
+}