/* * SSL/TLS interface functions for Microsoft Schannel * Copyright (c) 2005-2009, Jouni Malinen <j@w1.fi> * * This software may be distributed under the terms of the BSD license. * See README for more details. */ /* * FIX: Go through all SSPI functions and verify what needs to be freed * FIX: session resumption * TODO: add support for server cert chain validation * TODO: add support for CA cert validation * TODO: add support for EAP-TLS (client cert/key conf) */ #include "includes.h" #include <windows.h> #include <wincrypt.h> #include <schannel.h> #define SECURITY_WIN32 #include <security.h> #include <sspi.h> #include "common.h" #include "tls.h" struct tls_global { HMODULE hsecurity; PSecurityFunctionTable sspi; HCERTSTORE my_cert_store; }; struct tls_connection { int established, start; int failed, read_alerts, write_alerts; SCHANNEL_CRED schannel_cred; CredHandle creds; CtxtHandle context; u8 eap_tls_prf[128]; int eap_tls_prf_set; }; static int schannel_load_lib(struct tls_global *global) { INIT_SECURITY_INTERFACE pInitSecurityInterface; global->hsecurity = LoadLibrary(TEXT("Secur32.dll")); if (global->hsecurity == NULL) { wpa_printf(MSG_ERROR, "%s: Could not load Secur32.dll - 0x%x", __func__, (unsigned int) GetLastError()); return -1; } pInitSecurityInterface = (INIT_SECURITY_INTERFACE) GetProcAddress( global->hsecurity, "InitSecurityInterfaceA"); if (pInitSecurityInterface == NULL) { wpa_printf(MSG_ERROR, "%s: Could not find " "InitSecurityInterfaceA from Secur32.dll", __func__); FreeLibrary(global->hsecurity); global->hsecurity = NULL; return -1; } global->sspi = pInitSecurityInterface(); if (global->sspi == NULL) { wpa_printf(MSG_ERROR, "%s: Could not read security " "interface - 0x%x", __func__, (unsigned int) GetLastError()); FreeLibrary(global->hsecurity); global->hsecurity = NULL; return -1; } return 0; } void * tls_init(const struct tls_config *conf) { struct tls_global *global; global = os_zalloc(sizeof(*global)); if (global == NULL) return NULL; if (schannel_load_lib(global)) { os_free(global); return NULL; } return global; } void tls_deinit(void *ssl_ctx) { struct tls_global *global = ssl_ctx; if (global->my_cert_store) CertCloseStore(global->my_cert_store, 0); FreeLibrary(global->hsecurity); os_free(global); } int tls_get_errors(void *ssl_ctx) { return 0; } struct tls_connection * tls_connection_init(void *ssl_ctx) { struct tls_connection *conn; conn = os_zalloc(sizeof(*conn)); if (conn == NULL) return NULL; conn->start = 1; return conn; } void tls_connection_deinit(void *ssl_ctx, struct tls_connection *conn) { if (conn == NULL) return; os_free(conn); } int tls_connection_established(void *ssl_ctx, struct tls_connection *conn) { return conn ? conn->established : 0; } int tls_connection_shutdown(void *ssl_ctx, struct tls_connection *conn) { struct tls_global *global = ssl_ctx; if (conn == NULL) return -1; conn->eap_tls_prf_set = 0; conn->established = conn->failed = 0; conn->read_alerts = conn->write_alerts = 0; global->sspi->DeleteSecurityContext(&conn->context); /* FIX: what else needs to be reseted? */ return 0; } int tls_global_set_params(void *tls_ctx, const struct tls_connection_params *params) { return -1; } int tls_global_set_verify(void *ssl_ctx, int check_crl) { return -1; } int tls_connection_set_verify(void *ssl_ctx, struct tls_connection *conn, int verify_peer) { return -1; } int tls_connection_get_keys(void *ssl_ctx, struct tls_connection *conn, struct tls_keys *keys) { /* Schannel does not export master secret or client/server random. */ return -1; } int tls_connection_prf(void *tls_ctx, struct tls_connection *conn, const char *label, int server_random_first, u8 *out, size_t out_len) { /* * Cannot get master_key from Schannel, but EapKeyBlock can be used to * generate session keys for EAP-TLS and EAP-PEAPv0. EAP-PEAPv2 and * EAP-TTLS cannot use this, though, since they are using different * labels. The only option could be to implement TLSv1 completely here * and just use Schannel or CryptoAPI for low-level crypto * functionality.. */ if (conn == NULL || !conn->eap_tls_prf_set || server_random_first || os_strcmp(label, "client EAP encryption") != 0 || out_len > sizeof(conn->eap_tls_prf)) return -1; os_memcpy(out, conn->eap_tls_prf, out_len); return 0; } static struct wpabuf * tls_conn_hs_clienthello(struct tls_global *global, struct tls_connection *conn) { DWORD sspi_flags, sspi_flags_out; SecBufferDesc outbuf; SecBuffer outbufs[1]; SECURITY_STATUS status; TimeStamp ts_expiry; sspi_flags = ISC_REQ_REPLAY_DETECT | ISC_REQ_CONFIDENTIALITY | ISC_RET_EXTENDED_ERROR | ISC_REQ_ALLOCATE_MEMORY | ISC_REQ_MANUAL_CRED_VALIDATION; wpa_printf(MSG_DEBUG, "%s: Generating ClientHello", __func__); outbufs[0].pvBuffer = NULL; outbufs[0].BufferType = SECBUFFER_TOKEN; outbufs[0].cbBuffer = 0; outbuf.cBuffers = 1; outbuf.pBuffers = outbufs; outbuf.ulVersion = SECBUFFER_VERSION; #ifdef UNICODE status = global->sspi->InitializeSecurityContextW( &conn->creds, NULL, NULL /* server name */, sspi_flags, 0, SECURITY_NATIVE_DREP, NULL, 0, &conn->context, &outbuf, &sspi_flags_out, &ts_expiry); #else /* UNICODE */ status = global->sspi->InitializeSecurityContextA( &conn->creds, NULL, NULL /* server name */, sspi_flags, 0, SECURITY_NATIVE_DREP, NULL, 0, &conn->context, &outbuf, &sspi_flags_out, &ts_expiry); #endif /* UNICODE */ if (status != SEC_I_CONTINUE_NEEDED) { wpa_printf(MSG_ERROR, "%s: InitializeSecurityContextA " "failed - 0x%x", __func__, (unsigned int) status); return NULL; } if (outbufs[0].cbBuffer != 0 && outbufs[0].pvBuffer) { struct wpabuf *buf; wpa_hexdump(MSG_MSGDUMP, "SChannel - ClientHello", outbufs[0].pvBuffer, outbufs[0].cbBuffer); conn->start = 0; buf = wpabuf_alloc_copy(outbufs[0].pvBuffer, outbufs[0].cbBuffer); if (buf == NULL) return NULL; global->sspi->FreeContextBuffer(outbufs[0].pvBuffer); return buf; } wpa_printf(MSG_ERROR, "SChannel: Failed to generate ClientHello"); return NULL; } #ifndef SECPKG_ATTR_EAP_KEY_BLOCK #define SECPKG_ATTR_EAP_KEY_BLOCK 0x5b typedef struct _SecPkgContext_EapKeyBlock { BYTE rgbKeys[128]; BYTE rgbIVs[64]; } SecPkgContext_EapKeyBlock, *PSecPkgContext_EapKeyBlock; #endif /* !SECPKG_ATTR_EAP_KEY_BLOCK */ static int tls_get_eap(struct tls_global *global, struct tls_connection *conn) { SECURITY_STATUS status; SecPkgContext_EapKeyBlock kb; /* Note: Windows NT and Windows Me/98/95 do not support getting * EapKeyBlock */ status = global->sspi->QueryContextAttributes( &conn->context, SECPKG_ATTR_EAP_KEY_BLOCK, &kb); if (status != SEC_E_OK) { wpa_printf(MSG_DEBUG, "%s: QueryContextAttributes(" "SECPKG_ATTR_EAP_KEY_BLOCK) failed (%d)", __func__, (int) status); return -1; } wpa_hexdump_key(MSG_MSGDUMP, "Schannel - EapKeyBlock - rgbKeys", kb.rgbKeys, sizeof(kb.rgbKeys)); wpa_hexdump_key(MSG_MSGDUMP, "Schannel - EapKeyBlock - rgbIVs", kb.rgbIVs, sizeof(kb.rgbIVs)); os_memcpy(conn->eap_tls_prf, kb.rgbKeys, sizeof(kb.rgbKeys)); conn->eap_tls_prf_set = 1; return 0; } struct wpabuf * tls_connection_handshake(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data, struct wpabuf **appl_data) { struct tls_global *global = tls_ctx; DWORD sspi_flags, sspi_flags_out; SecBufferDesc inbuf, outbuf; SecBuffer inbufs[2], outbufs[1]; SECURITY_STATUS status; TimeStamp ts_expiry; struct wpabuf *out_buf = NULL; if (appl_data) *appl_data = NULL; if (conn->start) return tls_conn_hs_clienthello(global, conn); wpa_printf(MSG_DEBUG, "SChannel: %d bytes handshake data to process", (int) wpabuf_len(in_data)); sspi_flags = ISC_REQ_REPLAY_DETECT | ISC_REQ_CONFIDENTIALITY | ISC_RET_EXTENDED_ERROR | ISC_REQ_ALLOCATE_MEMORY | ISC_REQ_MANUAL_CRED_VALIDATION; /* Input buffer for Schannel */ inbufs[0].pvBuffer = (u8 *) wpabuf_head(in_data); inbufs[0].cbBuffer = wpabuf_len(in_data); inbufs[0].BufferType = SECBUFFER_TOKEN; /* Place for leftover data from Schannel */ inbufs[1].pvBuffer = NULL; inbufs[1].cbBuffer = 0; inbufs[1].BufferType = SECBUFFER_EMPTY; inbuf.cBuffers = 2; inbuf.pBuffers = inbufs; inbuf.ulVersion = SECBUFFER_VERSION; /* Output buffer for Schannel */ outbufs[0].pvBuffer = NULL; outbufs[0].cbBuffer = 0; outbufs[0].BufferType = SECBUFFER_TOKEN; outbuf.cBuffers = 1; outbuf.pBuffers = outbufs; outbuf.ulVersion = SECBUFFER_VERSION; #ifdef UNICODE status = global->sspi->InitializeSecurityContextW( &conn->creds, &conn->context, NULL, sspi_flags, 0, SECURITY_NATIVE_DREP, &inbuf, 0, NULL, &outbuf, &sspi_flags_out, &ts_expiry); #else /* UNICODE */ status = global->sspi->InitializeSecurityContextA( &conn->creds, &conn->context, NULL, sspi_flags, 0, SECURITY_NATIVE_DREP, &inbuf, 0, NULL, &outbuf, &sspi_flags_out, &ts_expiry); #endif /* UNICODE */ wpa_printf(MSG_MSGDUMP, "Schannel: InitializeSecurityContext -> " "status=%d inlen[0]=%d intype[0]=%d inlen[1]=%d " "intype[1]=%d outlen[0]=%d", (int) status, (int) inbufs[0].cbBuffer, (int) inbufs[0].BufferType, (int) inbufs[1].cbBuffer, (int) inbufs[1].BufferType, (int) outbufs[0].cbBuffer); if (status == SEC_E_OK || status == SEC_I_CONTINUE_NEEDED || (FAILED(status) && (sspi_flags_out & ISC_RET_EXTENDED_ERROR))) { if (outbufs[0].cbBuffer != 0 && outbufs[0].pvBuffer) { wpa_hexdump(MSG_MSGDUMP, "SChannel - output", outbufs[0].pvBuffer, outbufs[0].cbBuffer); out_buf = wpabuf_alloc_copy(outbufs[0].pvBuffer, outbufs[0].cbBuffer); global->sspi->FreeContextBuffer(outbufs[0].pvBuffer); outbufs[0].pvBuffer = NULL; if (out_buf == NULL) return NULL; } } switch (status) { case SEC_E_INCOMPLETE_MESSAGE: wpa_printf(MSG_DEBUG, "Schannel: SEC_E_INCOMPLETE_MESSAGE"); break; case SEC_I_CONTINUE_NEEDED: wpa_printf(MSG_DEBUG, "Schannel: SEC_I_CONTINUE_NEEDED"); break; case SEC_E_OK: /* TODO: verify server certificate chain */ wpa_printf(MSG_DEBUG, "Schannel: SEC_E_OK - Handshake " "completed successfully"); conn->established = 1; tls_get_eap(global, conn); /* Need to return something to get final TLS ACK. */ if (out_buf == NULL) out_buf = wpabuf_alloc(0); if (inbufs[1].BufferType == SECBUFFER_EXTRA) { wpa_hexdump(MSG_MSGDUMP, "SChannel - Encrypted " "application data", inbufs[1].pvBuffer, inbufs[1].cbBuffer); if (appl_data) { *appl_data = wpabuf_alloc_copy( outbufs[1].pvBuffer, outbufs[1].cbBuffer); } global->sspi->FreeContextBuffer(inbufs[1].pvBuffer); inbufs[1].pvBuffer = NULL; } break; case SEC_I_INCOMPLETE_CREDENTIALS: wpa_printf(MSG_DEBUG, "Schannel: SEC_I_INCOMPLETE_CREDENTIALS"); break; case SEC_E_WRONG_PRINCIPAL: wpa_printf(MSG_DEBUG, "Schannel: SEC_E_WRONG_PRINCIPAL"); break; case SEC_E_INTERNAL_ERROR: wpa_printf(MSG_DEBUG, "Schannel: SEC_E_INTERNAL_ERROR"); break; } if (FAILED(status)) { wpa_printf(MSG_DEBUG, "Schannel: Handshake failed " "(out_buf=%p)", out_buf); conn->failed++; global->sspi->DeleteSecurityContext(&conn->context); return out_buf; } if (inbufs[1].BufferType == SECBUFFER_EXTRA) { /* TODO: Can this happen? What to do with this data? */ wpa_hexdump(MSG_MSGDUMP, "SChannel - Leftover data", inbufs[1].pvBuffer, inbufs[1].cbBuffer); global->sspi->FreeContextBuffer(inbufs[1].pvBuffer); inbufs[1].pvBuffer = NULL; } return out_buf; } struct wpabuf * tls_connection_server_handshake(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data, struct wpabuf **appl_data) { return NULL; } struct wpabuf * tls_connection_encrypt(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data) { struct tls_global *global = tls_ctx; SECURITY_STATUS status; SecBufferDesc buf; SecBuffer bufs[4]; SecPkgContext_StreamSizes sizes; int i; struct wpabuf *out; status = global->sspi->QueryContextAttributes(&conn->context, SECPKG_ATTR_STREAM_SIZES, &sizes); if (status != SEC_E_OK) { wpa_printf(MSG_DEBUG, "%s: QueryContextAttributes failed", __func__); return NULL; } wpa_printf(MSG_DEBUG, "%s: Stream sizes: header=%u trailer=%u", __func__, (unsigned int) sizes.cbHeader, (unsigned int) sizes.cbTrailer); out = wpabuf_alloc(sizes.cbHeader + wpabuf_len(in_data) + sizes.cbTrailer); os_memset(&bufs, 0, sizeof(bufs)); bufs[0].pvBuffer = wpabuf_put(out, sizes.cbHeader); bufs[0].cbBuffer = sizes.cbHeader; bufs[0].BufferType = SECBUFFER_STREAM_HEADER; bufs[1].pvBuffer = wpabuf_put(out, 0); wpabuf_put_buf(out, in_data); bufs[1].cbBuffer = wpabuf_len(in_data); bufs[1].BufferType = SECBUFFER_DATA; bufs[2].pvBuffer = wpabuf_put(out, sizes.cbTrailer); bufs[2].cbBuffer = sizes.cbTrailer; bufs[2].BufferType = SECBUFFER_STREAM_TRAILER; buf.ulVersion = SECBUFFER_VERSION; buf.cBuffers = 3; buf.pBuffers = bufs; status = global->sspi->EncryptMessage(&conn->context, 0, &buf, 0); wpa_printf(MSG_MSGDUMP, "Schannel: EncryptMessage -> " "status=%d len[0]=%d type[0]=%d len[1]=%d type[1]=%d " "len[2]=%d type[2]=%d", (int) status, (int) bufs[0].cbBuffer, (int) bufs[0].BufferType, (int) bufs[1].cbBuffer, (int) bufs[1].BufferType, (int) bufs[2].cbBuffer, (int) bufs[2].BufferType); wpa_printf(MSG_MSGDUMP, "Schannel: EncryptMessage pointers: " "out_data=%p bufs %p %p %p", wpabuf_head(out), bufs[0].pvBuffer, bufs[1].pvBuffer, bufs[2].pvBuffer); for (i = 0; i < 3; i++) { if (bufs[i].pvBuffer && bufs[i].BufferType != SECBUFFER_EMPTY) { wpa_hexdump(MSG_MSGDUMP, "SChannel: bufs", bufs[i].pvBuffer, bufs[i].cbBuffer); } } if (status == SEC_E_OK) { wpa_printf(MSG_DEBUG, "%s: SEC_E_OK", __func__); wpa_hexdump_buf_key(MSG_MSGDUMP, "Schannel: Encrypted data " "from EncryptMessage", out); return out; } wpa_printf(MSG_DEBUG, "%s: Failed - status=%d", __func__, (int) status); wpabuf_free(out); return NULL; } struct wpabuf * tls_connection_decrypt(void *tls_ctx, struct tls_connection *conn, const struct wpabuf *in_data) { struct tls_global *global = tls_ctx; SECURITY_STATUS status; SecBufferDesc buf; SecBuffer bufs[4]; int i; struct wpabuf *out, *tmp; wpa_hexdump_buf(MSG_MSGDUMP, "Schannel: Encrypted data to DecryptMessage", in_data); os_memset(&bufs, 0, sizeof(bufs)); tmp = wpabuf_dup(in_data); if (tmp == NULL) return NULL; bufs[0].pvBuffer = wpabuf_mhead(tmp); bufs[0].cbBuffer = wpabuf_len(in_data); bufs[0].BufferType = SECBUFFER_DATA; bufs[1].BufferType = SECBUFFER_EMPTY; bufs[2].BufferType = SECBUFFER_EMPTY; bufs[3].BufferType = SECBUFFER_EMPTY; buf.ulVersion = SECBUFFER_VERSION; buf.cBuffers = 4; buf.pBuffers = bufs; status = global->sspi->DecryptMessage(&conn->context, &buf, 0, NULL); wpa_printf(MSG_MSGDUMP, "Schannel: DecryptMessage -> " "status=%d len[0]=%d type[0]=%d len[1]=%d type[1]=%d " "len[2]=%d type[2]=%d len[3]=%d type[3]=%d", (int) status, (int) bufs[0].cbBuffer, (int) bufs[0].BufferType, (int) bufs[1].cbBuffer, (int) bufs[1].BufferType, (int) bufs[2].cbBuffer, (int) bufs[2].BufferType, (int) bufs[3].cbBuffer, (int) bufs[3].BufferType); wpa_printf(MSG_MSGDUMP, "Schannel: DecryptMessage pointers: " "out_data=%p bufs %p %p %p %p", wpabuf_head(tmp), bufs[0].pvBuffer, bufs[1].pvBuffer, bufs[2].pvBuffer, bufs[3].pvBuffer); switch (status) { case SEC_E_INCOMPLETE_MESSAGE: wpa_printf(MSG_DEBUG, "%s: SEC_E_INCOMPLETE_MESSAGE", __func__); break; case SEC_E_OK: wpa_printf(MSG_DEBUG, "%s: SEC_E_OK", __func__); for (i = 0; i < 4; i++) { if (bufs[i].BufferType == SECBUFFER_DATA) break; } if (i == 4) { wpa_printf(MSG_DEBUG, "%s: No output data from " "DecryptMessage", __func__); wpabuf_free(tmp); return NULL; } wpa_hexdump_key(MSG_MSGDUMP, "Schannel: Decrypted data from " "DecryptMessage", bufs[i].pvBuffer, bufs[i].cbBuffer); out = wpabuf_alloc_copy(bufs[i].pvBuffer, bufs[i].cbBuffer); wpabuf_free(tmp); return out; } wpa_printf(MSG_DEBUG, "%s: Failed - status=%d", __func__, (int) status); wpabuf_free(tmp); return NULL; } int tls_connection_resumed(void *ssl_ctx, struct tls_connection *conn) { return 0; } int tls_connection_set_cipher_list(void *tls_ctx, struct tls_connection *conn, u8 *ciphers) { return -1; } int tls_get_cipher(void *ssl_ctx, struct tls_connection *conn, char *buf, size_t buflen) { return -1; } int tls_connection_enable_workaround(void *ssl_ctx, struct tls_connection *conn) { return 0; } int tls_connection_client_hello_ext(void *ssl_ctx, struct tls_connection *conn, int ext_type, const u8 *data, size_t data_len) { return -1; } int tls_connection_get_failed(void *ssl_ctx, struct tls_connection *conn) { if (conn == NULL) return -1; return conn->failed; } int tls_connection_get_read_alerts(void *ssl_ctx, struct tls_connection *conn) { if (conn == NULL) return -1; return conn->read_alerts; } int tls_connection_get_write_alerts(void *ssl_ctx, struct tls_connection *conn) { if (conn == NULL) return -1; return conn->write_alerts; } int tls_connection_set_params(void *tls_ctx, struct tls_connection *conn, const struct tls_connection_params *params) { struct tls_global *global = tls_ctx; ALG_ID algs[1]; SECURITY_STATUS status; TimeStamp ts_expiry; if (conn == NULL) return -1; if (global->my_cert_store == NULL && (global->my_cert_store = CertOpenSystemStore(0, TEXT("MY"))) == NULL) { wpa_printf(MSG_ERROR, "%s: CertOpenSystemStore failed - 0x%x", __func__, (unsigned int) GetLastError()); return -1; } os_memset(&conn->schannel_cred, 0, sizeof(conn->schannel_cred)); conn->schannel_cred.dwVersion = SCHANNEL_CRED_VERSION; conn->schannel_cred.grbitEnabledProtocols = SP_PROT_TLS1; algs[0] = CALG_RSA_KEYX; conn->schannel_cred.cSupportedAlgs = 1; conn->schannel_cred.palgSupportedAlgs = algs; conn->schannel_cred.dwFlags |= SCH_CRED_NO_DEFAULT_CREDS; #ifdef UNICODE status = global->sspi->AcquireCredentialsHandleW( NULL, UNISP_NAME_W, SECPKG_CRED_OUTBOUND, NULL, &conn->schannel_cred, NULL, NULL, &conn->creds, &ts_expiry); #else /* UNICODE */ status = global->sspi->AcquireCredentialsHandleA( NULL, UNISP_NAME_A, SECPKG_CRED_OUTBOUND, NULL, &conn->schannel_cred, NULL, NULL, &conn->creds, &ts_expiry); #endif /* UNICODE */ if (status != SEC_E_OK) { wpa_printf(MSG_DEBUG, "%s: AcquireCredentialsHandleA failed - " "0x%x", __func__, (unsigned int) status); return -1; } return 0; } unsigned int tls_capabilities(void *tls_ctx) { return 0; }