diff options
Diffstat (limited to 'tcpd/libcouriergnutls.c')
| -rw-r--r-- | tcpd/libcouriergnutls.c | 184 |
1 files changed, 183 insertions, 1 deletions
diff --git a/tcpd/libcouriergnutls.c b/tcpd/libcouriergnutls.c index 1b4bfe2..18ea01c 100644 --- a/tcpd/libcouriergnutls.c +++ b/tcpd/libcouriergnutls.c @@ -161,6 +161,23 @@ static void nonsslerror(struct tls_info *info, const char *pfix) (*info->tls_err_msg)(errmsg, info->app_data); } +#if HAVE_GNUTLS_ALPN + +static void sslerror(ssl_context ctx, int errcode, const char *pfix) +{ + char errmsg[512]; + const char *err; + + strcat(strcpy(errmsg, pfix), ": "); + + err=gnutls_strerror(errcode); + + strncat(errmsg, err, sizeof(errmsg)-1-strlen(errmsg)); + errmsg[sizeof(errmsg)-1]=0; + (*ctx->info_cpy.tls_err_msg)(errmsg, ctx->info_cpy.app_data); +} +#endif + static const char *safe_getenv(ssl_context context, const char *n, const char *def) { @@ -722,6 +739,154 @@ static int verify_client(ssl_handle ssl, int fd) return 0; } +#if HAVE_GNUTLS_ALPN +/* +** Parse the TLS_ALPN setting, repeatedly invoking a callback with: +** 1) size of the protocol string +** 2) the protocol string +** 3) pass-through parameter. +*/ + +static gnutls_alpn_flags_t alpn_parse(const char *alpn, + void (*cb)(unsigned char l, + const char *p, + void *arg), + void *arg) +{ + gnutls_alpn_flags_t flags=GNUTLS_ALPN_MANDATORY; + + while (alpn && *alpn) + { + const char *p; + unsigned char l; + + /* Commas and spaces are delimiters here */ + + if (*alpn==',' || isspace(*alpn)) + { + ++alpn; + continue; + } + + /* Look for the next comma, spaces, or end of string */ + p=alpn; + + while (*alpn && *alpn != ',' && !isspace(*alpn)) + ++alpn; + + /* + ** We now have the character count and the string. + ** Defend against a bad setting by checking for overflow. + */ + l=alpn - p; + + if (l != alpn - p) + continue; + + if (*p != '@') + (*cb)(l, p, arg); + else + { + if (l > 1) + switch (p[1]) { + case 'o': + case 'O': + flags &= GNUTLS_ALPN_MANDATORY; + break; + case 's': + case 'S': + flags |= GNUTLS_ALPN_SERVER_PRECEDENCE; + break; + } + } + } + + return flags; +} + +static void alpn_count(unsigned char l, + const char *p, + void *arg) +{ + ++*(unsigned *)arg; +} + +static void alpn_save(unsigned char l, + const char *name, + void *arg) +{ + gnutls_datum_t **p=(gnutls_datum_t **)arg; + + (*p)->data=(unsigned char *)name; + (*p)->size=l; + ++*p; +} + +static int alpn_set(ssl_context ctx, + gnutls_session_t session) +{ + const char *p=safe_getenv(ctx, "TLS_ALPN", ""); + unsigned n=0; + gnutls_datum_t *datums; + gnutls_datum_t *datum_ptr; + gnutls_alpn_flags_t flags; + int ret; + + alpn_parse(p, alpn_count, &n); + + if (n == 0) + return GNUTLS_E_SUCCESS; + + if ((datums=(gnutls_datum_t *)malloc(n * sizeof(gnutls_datum_t))) + == NULL) + { + return GNUTLS_E_SUCCESS; + } + + datum_ptr=datums; + + flags=alpn_parse(p, alpn_save, &datum_ptr); + + ret=gnutls_alpn_set_protocols(session, datums, n, flags); + free((char *)datums); + + return ret; +} + +#if 0 +static int verify_alpn(ssl_handle ssl) +{ + const char *p=safe_getenv(ssl->ctx, "TLS_ALPN", ""); + unsigned n=0; + + gnutls_datum_t protocol; + int rc; + + alpn_parse(p, alpn_count, &n); + + rc=gnutls_alpn_get_selected_protocol(ssl->session, &protocol); + if (rc == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) + { + fprintf(stderr, "Not negotiated\n"); + + return 0; + } + if (rc != GNUTLS_E_SUCCESS) + { + fprintf(stderr, "ERROR: %d %s\n", + rc, gnutls_strerror(rc)); + return 0; + } + + fprintf(stderr, "Negotiated "); + fwrite(protocol.data, protocol.size, 1, stderr); + fprintf(stderr, "\n"); + + return 0; +} +#endif +#endif + static int dohandshake(ssl_handle ssl, int fd, fd_set *r, fd_set *w) { int rc; @@ -734,10 +899,13 @@ static int dohandshake(ssl_handle ssl, int fd, fd_set *r, fd_set *w) { ssl->info_cpy.connect_interrupted=0; - if (verify_client(ssl, fd)) return -1; +#if 0 + if (verify_alpn(ssl)) + return -1; +#endif if (ssl->info_cpy.connect_callback != NULL && !(*ssl->info_cpy.connect_callback)(ssl, ssl->info_cpy.app_data)) @@ -1537,6 +1705,20 @@ RT | return NULL; } +#if HAVE_GNUTLS_ALPN + { + int result_rc; + + result_rc=alpn_set(ctx, ssl->session); + + if (result_rc != GNUTLS_E_SUCCESS) + { + sslerror(ctx, result_rc, "gnutls_alpn_set_protocols"); + tls_free_session(ssl); + return (NULL); + } + } +#endif if (ssl->dhparams_initialized) { gnutls_certificate_set_dh_params(ssl->xcred, ssl->dhparams); |