X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fjournal%2Fmicrohttpd-util.c;h=17135abf8b48dcf66be684c43d80ef60d9d2f38e;hp=b07ae6dff383c7eaa57ad35f1a7e87e8190d00a4;hb=f12be7e8ca278a5a207d0fd051acec700b804a7a;hpb=cafc7f91306ea17ace4a6c3d76d81c8780c87452 diff --git a/src/journal/microhttpd-util.c b/src/journal/microhttpd-util.c index b07ae6dff..17135abf8 100644 --- a/src/journal/microhttpd-util.c +++ b/src/journal/microhttpd-util.c @@ -3,6 +3,7 @@ /*** This file is part of systemd. + Copyright 2012 Lennart Poettering Copyright 2012 Zbigniew Jędrzejewski-Szmek systemd is free software; you can redistribute it and/or modify it @@ -21,12 +22,18 @@ #include #include +#include #include "microhttpd-util.h" #include "log.h" #include "macro.h" #include "util.h" +#ifdef HAVE_GNUTLS +#include +#include +#endif + void microhttpd_logger(void *arg, const char *fmt, va_list ap) { _cleanup_free_ char *f = NULL; @@ -40,6 +47,59 @@ void microhttpd_logger(void *arg, const char *fmt, va_list ap) { REENABLE_WARNING; } + +int respond_oom_internal(struct MHD_Connection *connection) { + struct MHD_Response *response; + const char m[] = "Out of memory.\n"; + int ret; + + assert(connection); + + response = MHD_create_response_from_buffer(sizeof(m)-1, (char*) m, MHD_RESPMEM_PERSISTENT); + if (!response) + return MHD_NO; + + MHD_add_response_header(response, "Content-Type", "text/plain"); + ret = MHD_queue_response(connection, MHD_HTTP_SERVICE_UNAVAILABLE, response); + MHD_destroy_response(response); + + return ret; +} + +_printf_(3,4) +int respond_error(struct MHD_Connection *connection, + unsigned code, + const char *format, ...) { + + struct MHD_Response *response; + char *m; + int r; + va_list ap; + + assert(connection); + assert(format); + + va_start(ap, format); + r = vasprintf(&m, format, ap); + va_end(ap); + + if (r < 0) + return respond_oom(connection); + + response = MHD_create_response_from_buffer(strlen(m), m, MHD_RESPMEM_MUST_FREE); + if (!response) { + free(m); + return respond_oom(connection); + } + + log_debug("queing response %u: %s", code, m); + MHD_add_response_header(response, "Content-Type", "text/plain"); + r = MHD_queue_response(connection, code, response); + MHD_destroy_response(response); + + return r; +} + #ifdef HAVE_GNUTLS static int log_level_map[] = { @@ -73,4 +133,133 @@ void log_func_gnutls(int level, const char *message) { log_meta(ourlevel, NULL, 0, NULL, "gnutls: %s", message); } +static int verify_cert_authorized(gnutls_session_t session) { + unsigned status; + gnutls_certificate_type_t type; + gnutls_datum_t out; + int r; + + r = gnutls_certificate_verify_peers2(session, &status); + if (r < 0) { + log_error("gnutls_certificate_verify_peers2 failed: %s", strerror(-r)); + return r; + } + + type = gnutls_certificate_type_get(session); + r = gnutls_certificate_verification_status_print(status, type, &out, 0); + if (r < 0) { + log_error("gnutls_certificate_verification_status_print failed: %s", strerror(-r)); + return r; + } + + log_info("Certificate status: %s", out.data); + + return status == 0 ? 0 : -EPERM; +} + +static int get_client_cert(gnutls_session_t session, gnutls_x509_crt_t *client_cert) { + const gnutls_datum_t *pcert; + unsigned listsize; + gnutls_x509_crt_t cert; + int r; + + assert(session); + assert(client_cert); + + pcert = gnutls_certificate_get_peers(session, &listsize); + if (!pcert || !listsize) { + log_error("Failed to retrieve certificate chain"); + return -EINVAL; + } + + r = gnutls_x509_crt_init(&cert); + if (r < 0) { + log_error("Failed to initialize client certificate"); + return r; + } + + /* Note that by passing values between 0 and listsize here, you + can get access to the CA's certs */ + r = gnutls_x509_crt_import(cert, &pcert[0], GNUTLS_X509_FMT_DER); + if (r < 0) { + log_error("Failed to import client certificate"); + gnutls_x509_crt_deinit(cert); + return r; + } + + *client_cert = cert; + return 0; +} + +static int get_auth_dn(gnutls_x509_crt_t client_cert, char **buf) { + size_t len = 0; + int r; + + assert(buf); + assert(*buf == NULL); + + r = gnutls_x509_crt_get_dn(client_cert, NULL, &len); + if (r != GNUTLS_E_SHORT_MEMORY_BUFFER) { + log_error("gnutls_x509_crt_get_dn failed"); + return r; + } + + *buf = malloc(len); + if (!*buf) + return log_oom(); + + gnutls_x509_crt_get_dn(client_cert, *buf, &len); + return 0; +} + +int check_permissions(struct MHD_Connection *connection, int *code) { + const union MHD_ConnectionInfo *ci; + gnutls_session_t session; + gnutls_x509_crt_t client_cert; + char _cleanup_free_ *buf = NULL; + int r; + + assert(connection); + assert(code); + + *code = 0; + + ci = MHD_get_connection_info(connection, + MHD_CONNECTION_INFO_GNUTLS_SESSION); + if (!ci) { + log_error("MHD_get_connection_info failed"); + return -EINVAL; + } + session = ci->tls_session; + assert(session); + + r = get_client_cert(session, &client_cert); + if (r < 0) { + *code = respond_error(connection, MHD_HTTP_UNAUTHORIZED, + "Authorization through certificate is required"); + return -EPERM; + } + + r = get_auth_dn(client_cert, &buf); + if (r < 0) { + *code = respond_error(connection, MHD_HTTP_UNAUTHORIZED, + "Failed to determine distinguished name from certificate"); + return -EPERM; + } + + log_info("Connection from %s", buf); + + r = verify_cert_authorized(session); + if (r < 0) { + log_error("Client is not authorized"); + *code = respond_error(connection, MHD_HTTP_UNAUTHORIZED, + "Client certificate not signed by recognized authority"); + } + return r; +} + +#else +int check_permissions(struct MHD_Connection *connection, int *code) { + return -EPERM; +} #endif