Subject: [PATCH] vtls: fix connection reuse checks for issuer cert and case sensitivity CVE-2021-22924 Reported-by: Harry Sintonen Bug: https://curl.se/docs/CVE-2021-22924.html CVE: CVE-2021-22924 Upstream-Status: backport from Ubuntu curl_7.68.0-1ubuntu2.6 Signed-off-by: Mike Crowe --- lib/url.c | 5 +++-- lib/urldata.h | 2 +- lib/vtls/gtls.c | 10 +++++----- lib/vtls/nss.c | 4 ++-- lib/vtls/openssl.c | 12 ++++++------ lib/vtls/vtls.c | 23 ++++++++++++++++++----- 6 files changed, 35 insertions(+), 21 deletions(-) diff --git a/lib/url.c b/lib/url.c index 47fc66aed..eebad8d32 100644 --- a/lib/url.c +++ b/lib/url.c @@ -3555,6 +3555,9 @@ static CURLcode create_conn(struct Curl_easy *data, data->set.proxy_ssl.primary.CApath = data->set.str[STRING_SSL_CAPATH_PROXY]; data->set.ssl.primary.CAfile = data->set.str[STRING_SSL_CAFILE_ORIG]; data->set.proxy_ssl.primary.CAfile = data->set.str[STRING_SSL_CAFILE_PROXY]; + data->set.ssl.primary.issuercert = data->set.str[STRING_SSL_ISSUERCERT_ORIG]; + data->set.proxy_ssl.primary.issuercert = + data->set.str[STRING_SSL_ISSUERCERT_PROXY]; data->set.ssl.primary.random_file = data->set.str[STRING_SSL_RANDOM_FILE]; data->set.proxy_ssl.primary.random_file = data->set.str[STRING_SSL_RANDOM_FILE]; @@ -3575,8 +3578,6 @@ static CURLcode create_conn(struct Curl_easy *data, data->set.ssl.CRLfile = data->set.str[STRING_SSL_CRLFILE_ORIG]; data->set.proxy_ssl.CRLfile = data->set.str[STRING_SSL_CRLFILE_PROXY]; - data->set.ssl.issuercert = data->set.str[STRING_SSL_ISSUERCERT_ORIG]; - data->set.proxy_ssl.issuercert = data->set.str[STRING_SSL_ISSUERCERT_PROXY]; data->set.ssl.cert = data->set.str[STRING_CERT_ORIG]; data->set.proxy_ssl.cert = data->set.str[STRING_CERT_PROXY]; data->set.ssl.cert_type = data->set.str[STRING_CERT_TYPE_ORIG]; diff --git a/lib/urldata.h b/lib/urldata.h index fbb8b645e..615fbf369 100644 --- a/lib/urldata.h +++ b/lib/urldata.h @@ -224,6 +224,7 @@ struct ssl_primary_config { long version_max; /* max supported version the client wants to use*/ char *CApath; /* certificate dir (doesn't work on windows) */ char *CAfile; /* certificate to verify peer against */ + char *issuercert; /* optional issuer certificate filename */ char *clientcert; char *random_file; /* path to file containing "random" data */ char *egdsocket; /* path to file containing the EGD daemon socket */ @@ -240,7 +241,6 @@ struct ssl_config_data { struct ssl_primary_config primary; long certverifyresult; /* result from the certificate verification */ char *CRLfile; /* CRL to check certificate revocation */ - char *issuercert;/* optional issuer certificate filename */ curl_ssl_ctx_callback fsslctx; /* function to initialize ssl ctx */ void *fsslctxp; /* parameter for call back */ char *cert; /* client certificate file name */ diff --git a/lib/vtls/gtls.c b/lib/vtls/gtls.c index 46e149c7d..8c051024f 100644 --- a/lib/vtls/gtls.c +++ b/lib/vtls/gtls.c @@ -1059,7 +1059,7 @@ gtls_connect_step3(struct connectdata *conn, if(!chainp) { if(SSL_CONN_CONFIG(verifypeer) || SSL_CONN_CONFIG(verifyhost) || - SSL_SET_OPTION(issuercert)) { + SSL_CONN_CONFIG(issuercert)) { #ifdef USE_TLS_SRP if(SSL_SET_OPTION(authtype) == CURL_TLSAUTH_SRP && SSL_SET_OPTION(username) != NULL @@ -1241,21 +1241,21 @@ gtls_connect_step3(struct connectdata *conn, gnutls_x509_crt_t format */ gnutls_x509_crt_import(x509_cert, chainp, GNUTLS_X509_FMT_DER); - if(SSL_SET_OPTION(issuercert)) { + if(SSL_CONN_CONFIG(issuercert)) { gnutls_x509_crt_init(&x509_issuer); - issuerp = load_file(SSL_SET_OPTION(issuercert)); + issuerp = load_file(SSL_CONN_CONFIG(issuercert)); gnutls_x509_crt_import(x509_issuer, &issuerp, GNUTLS_X509_FMT_PEM); rc = gnutls_x509_crt_check_issuer(x509_cert, x509_issuer); gnutls_x509_crt_deinit(x509_issuer); unload_file(issuerp); if(rc <= 0) { failf(data, "server certificate issuer check failed (IssuerCert: %s)", - SSL_SET_OPTION(issuercert)?SSL_SET_OPTION(issuercert):"none"); + SSL_CONN_CONFIG(issuercert)?SSL_CONN_CONFIG(issuercert):"none"); gnutls_x509_crt_deinit(x509_cert); return CURLE_SSL_ISSUER_ERROR; } infof(data, "\t server certificate issuer check OK (Issuer Cert: %s)\n", - SSL_SET_OPTION(issuercert)?SSL_SET_OPTION(issuercert):"none"); + SSL_CONN_CONFIG(issuercert)?SSL_CONN_CONFIG(issuercert):"none"); } size = sizeof(certbuf); diff --git a/lib/vtls/nss.c b/lib/vtls/nss.c index ef51b0d91..375c78b1b 100644 --- a/lib/vtls/nss.c +++ b/lib/vtls/nss.c @@ -2151,9 +2151,9 @@ static CURLcode nss_do_connect(struct connectdata *conn, int sockindex) if(result) goto error; - if(SSL_SET_OPTION(issuercert)) { + if(SSL_CONN_CONFIG(issuercert)) { SECStatus ret = SECFailure; - char *nickname = dup_nickname(data, SSL_SET_OPTION(issuercert)); + char *nickname = dup_nickname(data, SSL_CONN_CONFIG(issuercert)); if(nickname) { /* we support only nicknames in case of issuercert for now */ ret = check_issuer_cert(BACKEND->handle, nickname); diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c index 64f43605a..7e81fd3a0 100644 --- a/lib/vtls/openssl.c +++ b/lib/vtls/openssl.c @@ -3547,7 +3547,7 @@ static CURLcode servercert(struct connectdata *conn, deallocating the certificate. */ /* e.g. match issuer name with provided issuer certificate */ - if(SSL_SET_OPTION(issuercert)) { + if(SSL_CONN_CONFIG(issuercert)) { fp = BIO_new(BIO_s_file()); if(fp == NULL) { failf(data, @@ -3560,10 +3560,10 @@ static CURLcode servercert(struct connectdata *conn, return CURLE_OUT_OF_MEMORY; } - if(BIO_read_filename(fp, SSL_SET_OPTION(issuercert)) <= 0) { + if(BIO_read_filename(fp, SSL_CONN_CONFIG(issuercert)) <= 0) { if(strict) failf(data, "SSL: Unable to open issuer cert (%s)", - SSL_SET_OPTION(issuercert)); + SSL_CONN_CONFIG(issuercert)); BIO_free(fp); X509_free(BACKEND->server_cert); BACKEND->server_cert = NULL; @@ -3574,7 +3574,7 @@ static CURLcode servercert(struct connectdata *conn, if(!issuer) { if(strict) failf(data, "SSL: Unable to read issuer cert (%s)", - SSL_SET_OPTION(issuercert)); + SSL_CONN_CONFIG(issuercert)); BIO_free(fp); X509_free(issuer); X509_free(BACKEND->server_cert); @@ -3585,7 +3585,7 @@ static CURLcode servercert(struct connectdata *conn, if(X509_check_issued(issuer, BACKEND->server_cert) != X509_V_OK) { if(strict) failf(data, "SSL: Certificate issuer check failed (%s)", - SSL_SET_OPTION(issuercert)); + SSL_CONN_CONFIG(issuercert)); BIO_free(fp); X509_free(issuer); X509_free(BACKEND->server_cert); @@ -3594,7 +3594,7 @@ static CURLcode servercert(struct connectdata *conn, } infof(data, " SSL certificate issuer check ok (%s)\n", - SSL_SET_OPTION(issuercert)); + SSL_CONN_CONFIG(issuercert)); BIO_free(fp); X509_free(issuer); } diff --git a/lib/vtls/vtls.c b/lib/vtls/vtls.c index aaf73ef8f..8c681da14 100644 --- a/lib/vtls/vtls.c +++ b/lib/vtls/vtls.c @@ -82,6 +82,16 @@ else \ dest->var = NULL; +static bool safecmp(char *a, char *b) +{ + if(a && b) + return !strcmp(a, b); + else if(!a && !b) + return TRUE; /* match */ + return FALSE; /* no match */ +} + + bool Curl_ssl_config_matches(struct ssl_primary_config* data, struct ssl_primary_config* needle) @@ -91,11 +101,12 @@ Curl_ssl_config_matches(struct ssl_primary_config* data, (data->verifypeer == needle->verifypeer) && (data->verifyhost == needle->verifyhost) && (data->verifystatus == needle->verifystatus) && - Curl_safe_strcasecompare(data->CApath, needle->CApath) && - Curl_safe_strcasecompare(data->CAfile, needle->CAfile) && - Curl_safe_strcasecompare(data->clientcert, needle->clientcert) && - Curl_safe_strcasecompare(data->random_file, needle->random_file) && - Curl_safe_strcasecompare(data->egdsocket, needle->egdsocket) && + safecmp(data->CApath, needle->CApath) && + safecmp(data->CAfile, needle->CAfile) && + safecmp(data->issuercert, needle->issuercert) && + safecmp(data->clientcert, needle->clientcert) && + safecmp(data->random_file, needle->random_file) && + safecmp(data->egdsocket, needle->egdsocket) && Curl_safe_strcasecompare(data->cipher_list, needle->cipher_list) && Curl_safe_strcasecompare(data->cipher_list13, needle->cipher_list13) && Curl_safe_strcasecompare(data->pinned_key, needle->pinned_key)) @@ -117,6 +128,7 @@ Curl_clone_primary_ssl_config(struct ssl_primary_config *source, CLONE_STRING(CApath); CLONE_STRING(CAfile); + CLONE_STRING(issuercert); CLONE_STRING(clientcert); CLONE_STRING(random_file); CLONE_STRING(egdsocket); @@ -131,6 +143,7 @@ void Curl_free_primary_ssl_config(struct ssl_primary_config* sslc) { Curl_safefree(sslc->CApath); Curl_safefree(sslc->CAfile); + Curl_safefree(sslc->issuercert); Curl_safefree(sslc->clientcert); Curl_safefree(sslc->random_file); Curl_safefree(sslc->egdsocket); -- 2.30.2