libs/nixio/src/tls-socket.c

   1 /*
   2  * nixio - Linux I/O library for lua
   3  *
   4  *   Copyright (C) 2009 Steven Barth <steven@midlink.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "nixio-tls.h"
  20 #include <string.h>
  21 #include <stdlib.h>
  22
  23 static int nixio__tls_sock_perror(lua_State *L, SSL *sock, int code) {
  24         lua_pushnil(L);
  25         lua_pushinteger(L, SSL_get_error(sock, code));
  26         return 2;
  27 }
  28
  29 static int nixio__tls_sock_pstatus(lua_State *L, SSL *sock, int code) {
  30         if (code == 1) {
  31                 lua_pushboolean(L, 1);
  32                 return 1;
  33         } else {
  34                 return nixio__tls_sock_perror(L, sock, code);
  35         }
  36 }
  37
  38 static SSL* nixio__checktlssock(lua_State *L) {
  39         if (lua_istable(L, 1)) {
  40                 lua_getfield(L, 1, "connection");
  41                 lua_replace(L, 1);
  42         }
  43         nixio_tls_sock *sock = luaL_checkudata(L, 1, NIXIO_TLS_SOCK_META);
  44         luaL_argcheck(L, sock->socket, 1, "invalid context");
  45         return sock->socket;
  46 }
  47
  48 static int nixio_tls_sock_recv(lua_State *L) {
  49         SSL *sock = nixio__checktlssock(L);
  50         int req = luaL_checkinteger(L, 2);
  51
  52         luaL_argcheck(L, req >= 0, 2, "out of range");
  53
  54         /* We limit the readsize to NIXIO_BUFFERSIZE */
  55         req = (req > NIXIO_BUFFERSIZE) ? NIXIO_BUFFERSIZE : req;
  56
  57 #ifndef WITH_AXTLS
  58
  59         char buffer[NIXIO_BUFFERSIZE];
  60         int readc = SSL_read(sock, buffer, req);
  61
  62         if (readc < 0) {
  63                 return nixio__tls_sock_pstatus(L, sock, readc);
  64         } else {
  65                 lua_pushlstring(L, buffer, readc);
  66                 return 1;
  67         }
  68
  69 #else
  70
  71         if (!req) {
  72                 lua_pushliteral(L, "");
  73                 return 1;
  74         }
  75
  76         nixio_tls_sock *t = lua_touserdata(L, 1);
  77
  78         /* AXTLS doesn't handle buffering for us, so we have to hack around*/
  79         if (req < t->pbufsiz) {
  80                 lua_pushlstring(L, t->pbufpos, req);
  81                 t->pbufpos += req;
  82                 t->pbufsiz -= req;
  83                 return 1;
  84         } else {
  85                 char *axbuf;
  86                 int axread;
  87
  88                 /* while handshake pending */
  89                 while ((axread = ssl_read(sock, (uint8_t**)&axbuf)) == SSL_OK);
  90
  91                 if (t->pbufsiz) {
  92                         lua_pushlstring(L, t->pbufpos, t->pbufsiz);
  93                 }
  94
  95                 if (axread < 0) {
  96                         /* There is an error */
  97                         free(t->pbuffer);
  98                         t->pbuffer = t->pbufpos = NULL;
  99                         t->pbufsiz = 0;
 100
 101                         if (axread != SSL_ERROR_CONN_LOST) {
 102                                 return nixio__tls_sock_perror(L, sock, axread);
 103                         } else {
 104                                 if (!t->pbufsiz) {
 105                                         lua_pushliteral(L, "");
 106                                 }
 107                         }
 108                 } else {
 109                         int stillwant = req - t->pbufsiz;
 110                         if (stillwant < axread) {
 111                                 /* we got more data than we need */
 112                                 lua_pushlstring(L, axbuf, stillwant);
 113                                 if(t->pbufsiz) {
 114                                         lua_concat(L, 2);
 115                                 }
 116
 117                                 /* remaining data goes into the buffer */
 118                                 t->pbufpos = t->pbuffer;
 119                                 t->pbufsiz = axread - stillwant;
 120                                 t->pbuffer = realloc(t->pbuffer, t->pbufsiz);
 121                                 if (!t->pbuffer) {
 122                                         free(t->pbufpos);
 123                                         t->pbufpos = NULL;
 124                                         t->pbufsiz = 0;
 125                                         return luaL_error(L, "out of memory");
 126                                 }
 127
 128                                 t->pbufpos = t->pbuffer;
 129                                 memcpy(t->pbufpos, axbuf + stillwant, t->pbufsiz);
 130                         } else {
 131                                 lua_pushlstring(L, axbuf, axread);
 132                                 if(t->pbufsiz) {
 133                                         lua_concat(L, 2);
 134                                 }
 135
 136                                 /* free buffer */
 137                                 free(t->pbuffer);
 138                                 t->pbuffer = t->pbufpos = NULL;
 139                                 t->pbufsiz = 0;
 140                         }
 141                 }
 142                 return 1;
 143         }
 144
 145 #endif /* WITH_AXTLS */
 146
 147 }
 148
 149 static int nixio_tls_sock_send(lua_State *L) {
 150         SSL *sock = nixio__checktlssock(L);
 151         size_t len;
 152         ssize_t sent;
 153         const char *data = luaL_checklstring(L, 2, &len);
 154         sent = SSL_write(sock, data, len);
 155         if (sent > 0) {
 156                 lua_pushinteger(L, sent);
 157                 return 1;
 158         } else {
 159                 return nixio__tls_sock_pstatus(L, sock, len);
 160         }
 161 }
 162
 163 static int nixio_tls_sock_accept(lua_State *L) {
 164         SSL *sock = nixio__checktlssock(L);
 165         return nixio__tls_sock_pstatus(L, sock, SSL_accept(sock));
 166 }
 167
 168 static int nixio_tls_sock_connect(lua_State *L) {
 169         SSL *sock = nixio__checktlssock(L);
 170         return nixio__tls_sock_pstatus(L, sock, SSL_connect(sock));
 171 }
 172
 173 static int nixio_tls_sock_shutdown(lua_State *L) {
 174         SSL *sock = nixio__checktlssock(L);
 175         return nixio__tls_sock_pstatus(L, sock, SSL_shutdown(sock));
 176 }
 177
 178 static int nixio_tls_sock__gc(lua_State *L) {
 179         nixio_tls_sock *sock = luaL_checkudata(L, 1, NIXIO_TLS_SOCK_META);
 180         if (sock->socket) {
 181                 SSL_free(sock->socket);
 182                 sock->socket = NULL;
 183 #ifdef WITH_AXTLS
 184                 free(sock->pbuffer);
 185 #endif
 186         }
 187         return 0;
 188 }
 189
 190 static int nixio_tls_sock__tostring(lua_State *L) {
 191         SSL *sock = nixio__checktlssock(L);
 192         lua_pushfstring(L, "nixio TLS connection: %p", sock);
 193         return 1;
 194 }
 195
 196
 197 /* ctx function table */
 198 static const luaL_reg M[] = {
 199         {"recv",                nixio_tls_sock_recv},
 200         {"send",                nixio_tls_sock_send},
 201         {"accept",              nixio_tls_sock_accept},
 202         {"connect",     nixio_tls_sock_connect},
 203         {"shutdown",    nixio_tls_sock_shutdown},
 204         {"__gc",                nixio_tls_sock__gc},
 205         {"__tostring",  nixio_tls_sock__tostring},
 206         {NULL,                  NULL}
 207 };
 208
 209
 210 void nixio_open_tls_socket(lua_State *L) {
 211         /* create socket metatable */
 212         luaL_newmetatable(L, NIXIO_TLS_SOCK_META);
 213         luaL_register(L, NULL, M);
 214         lua_pushvalue(L, -1);
 215         lua_setfield(L, -2, "__index");
 216         lua_setfield(L, -2, "tls_socket_meta");
 217 }