libs/nixio/src/tls-context.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
  22 static SSL_CTX* nixio__checktlsctx(lua_State *L) {
  23         SSL_CTX **ctx = (SSL_CTX **)luaL_checkudata(L, 1, NIXIO_TLS_CTX_META);
  24         luaL_argcheck(L, *ctx, 1, "invalid context");
  25         return *ctx;
  26 }
  27
  28 static int nixio__tls_perror(lua_State *L, int code) {
  29         lua_pushnil(L);
  30         lua_pushinteger(L, code);
  31         return 2;
  32 }
  33
  34 static int nixio__tls_pstatus(lua_State *L, int code) {
  35         if (code == 1) {
  36                 lua_pushboolean(L, 1);
  37                 return 1;
  38         } else {
  39                 return nixio__tls_perror(L, code);
  40         }
  41 }
  42
  43 static int nixio_tls_ctx(lua_State * L) {
  44         const char *method = luaL_optlstring(L, 1, "tlsv1", NULL);
  45
  46         SSL_CTX **ctx = lua_newuserdata(L, sizeof(SSL_CTX *));
  47         if (!ctx) {
  48                 return luaL_error(L, "out of memory");
  49         }
  50
  51         /* create userdata */
  52         luaL_getmetatable(L, NIXIO_TLS_CTX_META);
  53         lua_setmetatable(L, -2);
  54
  55         if (!strcmp(method, "tlsv1")) {
  56                 *ctx = SSL_CTX_new(TLSv1_method());
  57         } else if (!strcmp(method, "sslv23")) {
  58                 *ctx = SSL_CTX_new(SSLv23_method());
  59         } else {
  60                 return luaL_argerror(L, 1, "supported values: tlsv1, sslv23");
  61         }
  62
  63
  64         SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
  65
  66         if (!(*ctx)) {
  67                 return luaL_error(L, "unable to create TLS context");
  68         }
  69
  70         return 1;
  71 }
  72
  73 static int nixio_tls_ctx_create(lua_State *L) {
  74         SSL_CTX *ctx = nixio__checktlsctx(L);
  75         int fd = nixio__checkfd(L, 2);
  76
  77         nixio_tls_sock *sock = lua_newuserdata(L, sizeof(nixio_tls_sock));
  78         if (!sock) {
  79                 return luaL_error(L, "out of memory");
  80         }
  81         memset(sock, 0, sizeof(nixio_tls_sock));
  82
  83         /* create userdata */
  84         luaL_getmetatable(L, NIXIO_TLS_SOCK_META);
  85         lua_setmetatable(L, -2);
  86
  87         sock->socket = SSL_new(ctx);
  88         if (!sock->socket) {
  89                 return nixio__tls_perror(L, 0);
  90         }
  91
  92         if (SSL_set_fd(sock->socket, fd) != 1) {
  93                 return nixio__tls_perror(L, 0);
  94         }
  95
  96         return 1;
  97 }
  98
  99 static int nixio_tls_ctx_set_cert(lua_State *L) {
 100         SSL_CTX *ctx = nixio__checktlsctx(L);
 101         const char *cert = luaL_checkstring(L, 2);
 102         return nixio__tls_pstatus(L, SSL_CTX_use_certificate_chain_file(ctx, cert));
 103 }
 104
 105 static int nixio_tls_ctx_set_key(lua_State *L) {
 106         SSL_CTX *ctx = nixio__checktlsctx(L);
 107         const char *cert = luaL_checkstring(L, 2);
 108         const int ktype = SSL_FILETYPE_PEM;
 109         return nixio__tls_pstatus(L, SSL_CTX_use_PrivateKey_file(ctx, cert, ktype));
 110 }
 111
 112 static int nixio_tls_ctx_set_ciphers(lua_State *L) {
 113         SSL_CTX *ctx = nixio__checktlsctx(L);
 114         size_t len;
 115         const char *ciphers = luaL_checklstring(L, 2, &len);
 116         luaL_argcheck(L, len < 255, 2, "cipher string too long");
 117         return nixio__tls_pstatus(L, SSL_CTX_set_cipher_list(ctx, ciphers));
 118 }
 119
 120 static int nixio_tls_ctx_set_verify_depth(lua_State *L) {
 121         SSL_CTX *ctx = nixio__checktlsctx(L);
 122         const int depth = luaL_checkinteger(L, 2);
 123         SSL_CTX_set_verify_depth(ctx, depth);
 124         return 0;
 125 }
 126
 127 static int nixio_tls_ctx_set_verify(lua_State *L) {
 128         SSL_CTX *ctx = nixio__checktlsctx(L);
 129         const int j = lua_gettop(L);
 130         int flags = 0;
 131         for (int i=2; i<=j; i++) {
 132                 const char *flag = luaL_checkstring(L, i);
 133                 if (!strcmp(flag, "none")) {
 134                         flags |= SSL_VERIFY_NONE;
 135                 } else if (!strcmp(flag, "peer")) {
 136                         flags |= SSL_VERIFY_PEER;
 137                 } else if (!strcmp(flag, "verify_fail_if_no_peer_cert")) {
 138                         flags |= SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
 139                 } else if (!strcmp(flag, "client_once")) {
 140                         flags |= SSL_VERIFY_CLIENT_ONCE;
 141                 } else {
 142                         return luaL_argerror(L, i, "supported values: none, peer, "
 143                          "verify_fail_if_no_peer_cert, client_once");
 144                 }
 145         }
 146         SSL_CTX_set_verify(ctx, flags, NULL);
 147         return 0;
 148 }
 149
 150 static int nixio_tls_ctx__gc(lua_State *L) {
 151         SSL_CTX **ctx = (SSL_CTX **)luaL_checkudata(L, 1, NIXIO_TLS_CTX_META);
 152         if (*ctx) {
 153                 SSL_CTX_free(*ctx);
 154                 *ctx = NULL;
 155         }
 156         return 0;
 157 }
 158
 159 static int nixio_tls_ctx__tostring(lua_State *L) {
 160         SSL_CTX *ctx = nixio__checktlsctx(L);
 161         lua_pushfstring(L, "nixio TLS context: %p", ctx);
 162         return 1;
 163 }
 164
 165 /* module table */
 166 static const luaL_reg R[] = {
 167         {"tls",         nixio_tls_ctx},
 168         {NULL,                  NULL}
 169 };
 170
 171 /* ctx function table */
 172 static const luaL_reg CTX_M[] = {
 173         {"set_cert",                    nixio_tls_ctx_set_cert},
 174         {"set_key",                             nixio_tls_ctx_set_key},
 175         {"set_ciphers",                 nixio_tls_ctx_set_ciphers},
 176         {"set_verify_depth",    nixio_tls_ctx_set_verify_depth},
 177         {"set_verify",                  nixio_tls_ctx_set_verify},
 178         {"create",                              nixio_tls_ctx_create},
 179         {"__gc",                                nixio_tls_ctx__gc},
 180         {"__tostring",                  nixio_tls_ctx__tostring},
 181         {NULL,                                  NULL}
 182 };
 183
 184
 185 void nixio_open_tls_context(lua_State *L) {
 186         /* initialize tls library */
 187     SSL_load_error_strings();
 188     SSL_library_init();
 189
 190     /* register module functions */
 191     luaL_register(L, NULL, R);
 192
 193         /* create context metatable */
 194         luaL_newmetatable(L, NIXIO_TLS_CTX_META);
 195         lua_pushvalue(L, -1);
 196         lua_setfield(L, -2, "__index");
 197         luaL_register(L, NULL, CTX_M);
 198         lua_pop(L, 1);
 199 }