ustream-polarssl.c

   1 /*
   2  * ustream-ssl - library for SSL over ustream
   3  *
   4  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/types.h>
  20 #include <fcntl.h>
  21 #include <unistd.h>
  22 #include <stdlib.h>
  23
  24 #include "ustream-ssl.h"
  25 #include "ustream-internal.h"
  26
  27 static int urandom_fd = -1;
  28
  29 static int s_ustream_read(void *ctx, unsigned char *buf, size_t len)
  30 {
  31         struct ustream *s = ctx;
  32         char *sbuf;
  33         int slen;
  34
  35         if (s->eof)
  36                 return 0;
  37
  38         sbuf = ustream_get_read_buf(s, &slen);
  39         if (slen > len)
  40                 slen = len;
  41
  42         if (!slen)
  43                 return POLARSSL_ERR_NET_WANT_READ;
  44
  45         memcpy(buf, sbuf, slen);
  46         ustream_consume(s, slen);
  47
  48         return slen;
  49 }
  50
  51 static int s_ustream_write(void *ctx, const unsigned char *buf, size_t len)
  52 {
  53         struct ustream *s = ctx;
  54
  55         len = ustream_write(s, (const char *) buf, len, false);
  56         if (len < 0 || s->write_error)
  57                 return POLARSSL_ERR_NET_SEND_FAILED;
  58
  59         return len;
  60 }
  61
  62 __hidden void ustream_set_io(void *ctx, void *ssl, struct ustream *conn)
  63 {
  64         ssl_set_bio(ssl, s_ustream_read, conn, s_ustream_write, conn);
  65 }
  66
  67 static bool urandom_init(void)
  68 {
  69         if (urandom_fd > -1)
  70                 return true;
  71
  72         urandom_fd = open("/dev/urandom", O_RDONLY);
  73         if (urandom_fd < 0)
  74                 return false;
  75
  76         return true;
  77 }
  78
  79 static int _urandom(void *ctx, unsigned char *out, size_t len)
  80 {
  81         read(urandom_fd, out, len);
  82         return 0;
  83 }
  84
  85 __hidden void * __ustream_ssl_context_new(bool server)
  86 {
  87         struct ustream_polarssl_ctx *uctx;
  88
  89         if (!urandom_init())
  90                 return NULL;
  91
  92         uctx = calloc(1, sizeof(*uctx));
  93         if (!uctx)
  94                 return NULL;
  95
  96         uctx->server = server;
  97         rsa_init(&uctx->key, RSA_PKCS_V15, 0);
  98
  99         return uctx;
 100 }
 101
 102 __hidden int __ustream_ssl_set_crt_file(void *ctx, const char *file)
 103 {
 104         struct ustream_polarssl_ctx *uctx = ctx;
 105
 106         if (x509parse_crtfile(&uctx->cert, file))
 107                 return -1;
 108
 109         return 0;
 110 }
 111
 112 __hidden int __ustream_ssl_set_key_file(void *ctx, const char *file)
 113 {
 114         struct ustream_polarssl_ctx *uctx = ctx;
 115
 116         if (x509parse_keyfile(&uctx->key, file, NULL))
 117                 return -1;
 118
 119         return 0;
 120 }
 121
 122 __hidden void __ustream_ssl_context_free(void *ctx)
 123 {
 124         struct ustream_polarssl_ctx *uctx = ctx;
 125
 126         rsa_free(&uctx->key);
 127         x509_free(&uctx->cert);
 128         free(ctx);
 129 }
 130
 131 static void ustream_ssl_error(struct ustream_ssl *us, int ret)
 132 {
 133         us->error = ret;
 134         uloop_timeout_set(&us->error_timer, 0);
 135 }
 136
 137 static bool ssl_do_wait(int ret)
 138 {
 139         switch(ret) {
 140         case POLARSSL_ERR_NET_WANT_READ:
 141         case POLARSSL_ERR_NET_WANT_WRITE:
 142                 return true;
 143         default:
 144                 return false;
 145         }
 146 }
 147
 148 __hidden enum ssl_conn_status __ustream_ssl_connect(struct ustream_ssl *us)
 149 {
 150         void *ssl = us->ssl;
 151         int r;
 152
 153         r = ssl_handshake(ssl);
 154         if (r == 0)
 155                 return U_SSL_OK;
 156
 157         if (ssl_do_wait(r))
 158                 return U_SSL_PENDING;
 159
 160         ustream_ssl_error(us, r);
 161         return U_SSL_ERROR;
 162 }
 163
 164 __hidden int __ustream_ssl_write(struct ustream_ssl *us, const char *buf, int len)
 165 {
 166         void *ssl = us->ssl;
 167         int ret = ssl_write(ssl, (const unsigned char *) buf, len);
 168
 169         if (ret < 0) {
 170                 if (ssl_do_wait(ret))
 171                         return 0;
 172
 173                 ustream_ssl_error(us, ret);
 174                 return -1;
 175         }
 176
 177         return ret;
 178 }
 179
 180 __hidden int __ustream_ssl_read(struct ustream_ssl *us, char *buf, int len)
 181 {
 182         int ret = ssl_read(us->ssl, (unsigned char *) buf, len);
 183
 184         if (ret < 0) {
 185                 if (ssl_do_wait(ret))
 186                         return U_SSL_PENDING;
 187
 188                 ustream_ssl_error(us, ret);
 189                 return U_SSL_ERROR;
 190         }
 191
 192         return ret;
 193 }
 194
 195 __hidden void *__ustream_ssl_session_new(void *ctx)
 196 {
 197         struct ustream_polarssl_ctx *uctx = ctx;
 198         ssl_context *ssl;
 199         int ep, auth;
 200
 201         ssl = calloc(1, sizeof(ssl_context));
 202         if (!ssl)
 203                 return NULL;
 204
 205         if (ssl_init(ssl)) {
 206                 free(ssl);
 207                 return NULL;
 208         }
 209
 210         if (uctx->server) {
 211                 ep = SSL_IS_SERVER;
 212                 auth = SSL_VERIFY_NONE;
 213         } else {
 214                 ep = SSL_IS_CLIENT;
 215                 auth = SSL_VERIFY_OPTIONAL;
 216         }
 217
 218         ssl_set_endpoint(ssl, ep);
 219         ssl_set_authmode(ssl, auth);
 220         ssl_set_rng(ssl, _urandom, NULL);
 221
 222         if (uctx->server) {
 223                 if (uctx->cert.next)
 224                         ssl_set_ca_chain(ssl, uctx->cert.next, NULL, NULL);
 225                 ssl_set_own_cert(ssl, &uctx->cert, &uctx->key);
 226         }
 227
 228         ssl_session_reset(ssl);
 229
 230         return ssl;
 231 }
 232
 233 __hidden void __ustream_ssl_session_free(void *ssl)
 234 {
 235         ssl_free(ssl);
 236         free(ssl);
 237 }