From 399c2da08ab9c6a382f8e9950742a022e847fec0 Mon Sep 17 00:00:00 2001 From: Kurt Roeckx Date: Sun, 18 Dec 2022 20:54:15 +0100 Subject: Update X509 fuzzer to verify a chain It add supports for verifying that it's been signed by a CA, and checks the CRL and OCSP status Can find CVE-2022-4203 and CVE-2023-0286 Reviewed-by: Bernd Edlinger Reviewed-by: Tomas Mraz Reviewed-by: Dmitry Belyavskiy Reviewed-by: Hugo Landau (Merged from https://github.com/openssl/openssl/pull/20243) --- fuzz/build.info | 12 +++++- fuzz/x509.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 122 insertions(+), 13 deletions(-) (limited to 'fuzz') diff --git a/fuzz/build.info b/fuzz/build.info index e20034cfee..7efc52ef85 100644 --- a/fuzz/build.info +++ b/fuzz/build.info @@ -9,7 +9,7 @@ -} IF[{- !$disabled{"fuzz-afl"} || !$disabled{"fuzz-libfuzzer"} -}] - PROGRAMS{noinst}=asn1 asn1parse bignum bndiv client conf crl server smime x509 + PROGRAMS{noinst}=asn1 asn1parse bignum bndiv client conf crl server smime PROGRAMS{noinst}=punycode pem decoder PROGRAMS{noinst}=v3name @@ -25,6 +25,10 @@ IF[{- !$disabled{"fuzz-afl"} || !$disabled{"fuzz-libfuzzer"} -}] PROGRAMS{noinst}=ct ENDIF + IF[{- !$disabled{"ocsp"} -}] + PROGRAMS{noinst}=x509 + ENDIF + SOURCE[asn1]=asn1.c driver.c fuzz_rand.c INCLUDE[asn1]=../include {- $ex_inc -} DEPEND[asn1]=../libcrypto ../libssl {- $ex_lib -} @@ -95,7 +99,7 @@ IF[{- !$disabled{"fuzz-afl"} || !$disabled{"fuzz-libfuzzer"} -}] ENDIF IF[{- !$disabled{tests} -}] - PROGRAMS{noinst}=asn1-test asn1parse-test bignum-test bndiv-test client-test conf-test crl-test server-test smime-test x509-test + PROGRAMS{noinst}=asn1-test asn1parse-test bignum-test bndiv-test client-test conf-test crl-test server-test smime-test PROGRAMS{noinst}=punycode-test pem-test decoder-test PROGRAMS{noinst}=v3name-test @@ -111,6 +115,10 @@ IF[{- !$disabled{tests} -}] PROGRAMS{noinst}=ct-test ENDIF + IF[{- !$disabled{"ocsp"} -}] + PROGRAMS{noinst}=x509-test + ENDIF + SOURCE[asn1-test]=asn1.c test-corpus.c fuzz_rand.c INCLUDE[asn1-test]=../include DEPEND[asn1-test]=../libcrypto ../libssl diff --git a/fuzz/x509.c b/fuzz/x509.c index 78061d176a..6293f1a5c5 100644 --- a/fuzz/x509.c +++ b/fuzz/x509.c @@ -9,6 +9,7 @@ */ #include +#include #include #include #include @@ -17,31 +18,131 @@ int FuzzerInitialize(int *argc, char ***argv) { FuzzerSetRand(); - OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS, NULL); + OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CRYPTO_STRINGS + | OPENSSL_INIT_ADD_ALL_CIPHERS | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL); ERR_clear_error(); CRYPTO_free_ex_index(0, -1); return 1; } +static int cb(int ok, X509_STORE_CTX *ctx) +{ + return 1; +} + int FuzzerTestOneInput(const uint8_t *buf, size_t len) { const unsigned char *p = buf; + size_t orig_len = len; unsigned char *der = NULL; + BIO *bio = NULL; + X509 *x509_1 = NULL, *x509_2 = NULL; + X509_STORE *store = NULL; + X509_VERIFY_PARAM *param = NULL; + X509_STORE_CTX *ctx = NULL; + X509_CRL *crl = NULL; + STACK_OF(X509_CRL) *crls = NULL; + STACK_OF(X509) *certs = NULL; + OCSP_RESPONSE *resp = NULL; + OCSP_BASICRESP *bs = NULL; + OCSP_CERTID *id = NULL; + + x509_1 = d2i_X509(NULL, &p, len); + if (x509_1 == NULL) + goto err; + + bio = BIO_new(BIO_s_null()); + if (bio == NULL) + goto err; + + /* This will load and print the public key as well as extensions */ + X509_print(bio, x509_1); + BIO_free(bio); + + X509_issuer_and_serial_hash(x509_1); + + i2d_X509(x509_1, &der); + OPENSSL_free(der); + + len = orig_len - (p - buf); + x509_2 = d2i_X509(NULL, &p, len); + if (x509_2 == NULL) + goto err; + + len = orig_len - (p - buf); + crl = d2i_X509_CRL(NULL, &p, len); + if (crl == NULL) + goto err; + + len = orig_len - (p - buf); + resp = d2i_OCSP_RESPONSE(NULL, &p, len); + + store = X509_STORE_new(); + X509_STORE_add_cert(store, x509_2); - X509 *x509 = d2i_X509(NULL, &p, len); - if (x509 != NULL) { - BIO *bio = BIO_new(BIO_s_null()); - /* This will load and print the public key as well as extensions */ - X509_print(bio, x509); - BIO_free(bio); + param = X509_VERIFY_PARAM_new(); + X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_NO_CHECK_TIME); + X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_X509_STRICT); + X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_PARTIAL_CHAIN); + X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK); - X509_issuer_and_serial_hash(x509); + X509_STORE_set1_param(store, param); - i2d_X509(x509, &der); - OPENSSL_free(der); + X509_STORE_set_verify_cb(store, cb); - X509_free(x509); + ctx = X509_STORE_CTX_new(); + if (ctx == NULL) + goto err; + + X509_STORE_CTX_init(ctx, store, x509_1, NULL); + + if (crl != NULL) { + crls = sk_X509_CRL_new_null(); + if (crls == NULL) + goto err; + + sk_X509_CRL_push(crls, crl); + X509_STORE_CTX_set0_crls(ctx, crls); } + + X509_verify_cert(ctx); + + if (resp != NULL) + bs = OCSP_response_get1_basic(resp); + + if (bs != NULL) { + int status, reason; + ASN1_GENERALIZEDTIME *revtime, *thisupd, *nextupd; + + certs = sk_X509_new_null(); + if (certs == NULL) + goto err; + + sk_X509_push(certs, x509_1); + sk_X509_push(certs, x509_2); + + OCSP_basic_verify(bs, certs, store, OCSP_PARTIAL_CHAIN); + + id = OCSP_cert_to_id(NULL, x509_1, x509_2); + if (id == NULL) + goto err; + OCSP_resp_find_status(bs, id, &status, &reason, &revtime, &thisupd, + &nextupd); + } + +err: + X509_STORE_CTX_free(ctx); + X509_VERIFY_PARAM_free(param); + X509_STORE_free(store); + X509_free(x509_1); + X509_free(x509_2); + X509_CRL_free(crl); + OCSP_CERTID_free(id); + OCSP_BASICRESP_free(bs); + OCSP_RESPONSE_free(resp); + sk_X509_CRL_free(crls); + sk_X509_free(certs); + ERR_clear_error(); return 0; } -- cgit v1.2.3