diff options
Diffstat (limited to 'lib/vtls/wolfssl.c')
| -rw-r--r-- | lib/vtls/wolfssl.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/lib/vtls/wolfssl.c b/lib/vtls/wolfssl.c index f022f93c1..8f7dd3abd 100644 --- a/lib/vtls/wolfssl.c +++ b/lib/vtls/wolfssl.c @@ -63,6 +63,7 @@ #include "sendf.h" #include "inet_pton.h" #include "vtls.h" +#include "keylog.h" #include "parsedate.h" #include "connect.h" /* for the connect timeout */ #include "select.h" @@ -99,6 +100,107 @@ struct ssl_backend_data { static Curl_recv wolfssl_recv; static Curl_send wolfssl_send; +#ifdef OPENSSL_EXTRA +/* + * Availability note: + * The TLS 1.3 secret callback (wolfSSL_set_tls13_secret_cb) was added in + * WolfSSL 4.4.0, but requires the -DHAVE_SECRET_CALLBACK build option. If that + * option is not set, then TLS 1.3 will not be logged. + * For TLS 1.2 and before, we use wolfSSL_get_keys(). + * SSL_get_client_random and wolfSSL_get_keys require OPENSSL_EXTRA + * (--enable-opensslextra or --enable-all). + */ +#if defined(HAVE_SECRET_CALLBACK) && defined(WOLFSSL_TLS13) +static int +wolfssl_tls13_secret_callback(SSL *ssl, int id, const unsigned char *secret, + int secretSz, void *ctx) +{ + const char *label; + unsigned char client_random[SSL3_RANDOM_SIZE]; + (void)ctx; + + if(!ssl || !Curl_tls_keylog_enabled()) { + return 0; + } + + switch(id) { + case CLIENT_EARLY_TRAFFIC_SECRET: + label = "CLIENT_EARLY_TRAFFIC_SECRET"; + break; + case CLIENT_HANDSHAKE_TRAFFIC_SECRET: + label = "CLIENT_HANDSHAKE_TRAFFIC_SECRET"; + break; + case SERVER_HANDSHAKE_TRAFFIC_SECRET: + label = "SERVER_HANDSHAKE_TRAFFIC_SECRET"; + break; + case CLIENT_TRAFFIC_SECRET: + label = "CLIENT_TRAFFIC_SECRET_0"; + break; + case SERVER_TRAFFIC_SECRET: + label = "SERVER_TRAFFIC_SECRET_0"; + break; + case EARLY_EXPORTER_SECRET: + label = "EARLY_EXPORTER_SECRET"; + break; + case EXPORTER_SECRET: + label = "EXPORTER_SECRET"; + break; + default: + return 0; + } + + if(SSL_get_client_random(ssl, client_random, SSL3_RANDOM_SIZE) == 0) { + /* Should never happen as wolfSSL_KeepArrays() was called before. */ + return 0; + } + + Curl_tls_keylog_write(label, client_random, secret, secretSz); + return 0; +} +#endif /* defined(HAVE_SECRET_CALLBACK) && defined(WOLFSSL_TLS13) */ + +static void +wolfssl_log_tls12_secret(SSL *ssl) +{ + unsigned char *ms, *sr, *cr; + unsigned int msLen, srLen, crLen, i, x = 0; + +#if LIBWOLFSSL_VERSION_HEX >= 0x0300d000 /* >= 3.13.0 */ + /* wolfSSL_GetVersion is available since 3.13, we use it instead of + * SSL_version since the latter relies on OPENSSL_ALL (--enable-opensslall or + * --enable-all). Failing to perform this check could result in an unusable + * key log line when TLS 1.3 is actually negotiated. */ + switch(wolfSSL_GetVersion(ssl)) { + case WOLFSSL_SSLV3: + case WOLFSSL_TLSV1: + case WOLFSSL_TLSV1_1: + case WOLFSSL_TLSV1_2: + break; + default: + /* TLS 1.3 does not use this mechanism, the "master secret" returned below + * is not directly usable. */ + return; + } +#endif + + if(SSL_get_keys(ssl, &ms, &msLen, &sr, &srLen, &cr, &crLen) != SSL_SUCCESS) { + return; + } + + /* Check for a missing master secret and skip logging. That can happen if + * curl rejects the server certificate and aborts the handshake. + */ + for(i = 0; i < msLen; i++) { + x |= ms[i]; + } + if(x == 0) { + return; + } + + Curl_tls_keylog_write("CLIENT_RANDOM", cr, ms, msLen); +} +#endif /* OPENSSL_EXTRA */ + static int do_file_type(const char *type) { if(!type || !type[0]) @@ -385,6 +487,17 @@ wolfssl_connect_step1(struct connectdata *conn, } #endif /* HAVE_ALPN */ +#ifdef OPENSSL_EXTRA + if(Curl_tls_keylog_enabled()) { + /* Ensure the Client Random is preserved. */ + wolfSSL_KeepArrays(backend->handle); +#if defined(HAVE_SECRET_CALLBACK) && defined(WOLFSSL_TLS13) + wolfSSL_set_tls13_secret_cb(backend->handle, + wolfssl_tls13_secret_callback, NULL); +#endif + } +#endif /* OPENSSL_EXTRA */ + /* Check if there's a cached ID we can/should use here! */ if(SSL_SET_OPTION(primary.sessionid)) { void *ssl_sessionid = NULL; @@ -444,6 +557,31 @@ wolfssl_connect_step2(struct connectdata *conn, } ret = SSL_connect(backend->handle); + +#ifdef OPENSSL_EXTRA + if(Curl_tls_keylog_enabled()) { + /* If key logging is enabled, wait for the handshake to complete and then + * proceed with logging secrets (for TLS 1.2 or older). + * + * During the handshake (ret==-1), wolfSSL_want_read() is true as it waits + * for the server response. At that point the master secret is not yet + * available, so we must not try to read it. + * To log the secret on completion with a handshake failure, detect + * completion via the observation that there is nothing to read or write. + * Note that OpenSSL SSL_want_read() is always true here. If wolfSSL ever + * changes, the worst case is that no key is logged on error. + */ + if(ret == SSL_SUCCESS || + (!wolfSSL_want_read(backend->handle) && + !wolfSSL_want_write(backend->handle))) { + wolfssl_log_tls12_secret(backend->handle); + /* Client Random and master secrets are no longer needed, erase these. + * Ignored while the handshake is still in progress. */ + wolfSSL_FreeArrays(backend->handle); + } + } +#endif /* OPENSSL_EXTRA */ + if(ret != 1) { char error_buffer[WOLFSSL_MAX_ERROR_SZ]; int detail = SSL_get_error(backend->handle, ret); @@ -750,6 +888,9 @@ static size_t Curl_wolfssl_version(char *buffer, size_t size) static int Curl_wolfssl_init(void) { +#ifdef OPENSSL_EXTRA + Curl_tls_keylog_open(); +#endif return (wolfSSL_Init() == SSL_SUCCESS); } @@ -757,6 +898,9 @@ static int Curl_wolfssl_init(void) static void Curl_wolfssl_cleanup(void) { wolfSSL_Cleanup(); +#ifdef OPENSSL_EXTRA + Curl_tls_keylog_close(); +#endif } |