lib/pdu.c

   1 /*
   2    Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as published by
   6    the Free Software Foundation; either version 2.1 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18 #if defined(WIN32)
  19 #include <winsock2.h>
  20 #define MSG_DONTWAIT 0
  21 #else
  22 #include <strings.h>
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <errno.h>
  28 #include <rpc/rpc.h>
  29 #include <rpc/xdr.h>
  30 #include <rpc/rpc_msg.h>
  31 #include "slist.h"
  32 #include "libnfs.h"
  33 #include "libnfs-raw.h"
  34 #include "libnfs-private.h"
  35
  36 struct rpc_pdu *rpc_allocate_pdu(struct rpc_context *rpc, int program, int version, int procedure, rpc_cb cb, void *private_data, xdrproc_t xdr_decode_fn, int xdr_decode_bufsize)
  37 {
  38         struct rpc_pdu *pdu;
  39         struct rpc_msg msg;
  40
  41         if (rpc == NULL) {
  42                 return NULL;
  43         }
  44
  45         pdu = malloc(sizeof(struct rpc_pdu));
  46         if (pdu == NULL) {
  47                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  48                 return NULL;
  49         }
  50         memset(pdu, 0, sizeof(struct rpc_pdu));
  51         pdu->xid                = rpc->xid++;
  52         pdu->cb                 = cb;
  53         pdu->private_data       = private_data;
  54         pdu->xdr_decode_fn      = xdr_decode_fn;
  55         pdu->xdr_decode_bufsize = xdr_decode_bufsize;
  56
  57         xdrmem_create(&pdu->xdr, rpc->encodebuf, rpc->encodebuflen, XDR_ENCODE);
  58         if (rpc->is_udp == 0) {
  59                 xdr_setpos(&pdu->xdr, 4); /* skip past the record marker */
  60         }
  61
  62         memset(&msg, 0, sizeof(struct rpc_msg));
  63         msg.rm_xid = pdu->xid;
  64         msg.rm_direction = CALL;
  65         msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
  66         msg.rm_call.cb_prog = program;
  67         msg.rm_call.cb_vers = version;
  68         msg.rm_call.cb_proc = procedure;
  69         msg.rm_call.cb_cred = rpc->auth->ah_cred;
  70         msg.rm_call.cb_verf = rpc->auth->ah_verf;
  71
  72         if (xdr_callmsg(&pdu->xdr, &msg) == 0) {
  73                 rpc_set_error(rpc, "xdr_callmsg failed");
  74                 xdr_destroy(&pdu->xdr);
  75                 free(pdu);
  76                 return NULL;
  77         }
  78
  79         return pdu;
  80 }
  81
  82 void rpc_free_pdu(struct rpc_context *rpc _U_, struct rpc_pdu *pdu)
  83 {
  84         if (pdu->outdata.data != NULL) {
  85                 free(pdu->outdata.data);
  86                 pdu->outdata.data = NULL;
  87         }
  88
  89         if (pdu->xdr_decode_buf != NULL) {
  90                 xdr_free(pdu->xdr_decode_fn, pdu->xdr_decode_buf);
  91                 free(pdu->xdr_decode_buf);
  92                 pdu->xdr_decode_buf = NULL;
  93         }
  94
  95         xdr_destroy(&pdu->xdr);
  96
  97         free(pdu);
  98 }
  99
 100
 101 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 102 {
 103         int size, recordmarker;
 104
 105         size = xdr_getpos(&pdu->xdr);
 106
 107         /* for udp we dont queue, we just send it straight away */
 108         if (rpc->is_udp != 0) {
 109                 if (sendto(rpc->fd, rpc->encodebuf, size, MSG_DONTWAIT, rpc->udp_dest, sizeof(struct sockaddr_in)) < 0) {
 110                         rpc_set_error(rpc, "Sendto failed with errno %s", strerror(errno));
 111                         rpc_free_pdu(rpc, pdu);
 112                         return -1;
 113                 }
 114                 SLIST_ADD_END(&rpc->waitpdu, pdu);
 115                 return 0;
 116         }
 117
 118         /* write recordmarker */
 119         xdr_setpos(&pdu->xdr, 0);
 120         recordmarker = (size - 4) | 0x80000000;
 121         xdr_int(&pdu->xdr, &recordmarker);
 122
 123         pdu->outdata.size = size;
 124         pdu->outdata.data = malloc(pdu->outdata.size);
 125         if (pdu->outdata.data == NULL) {
 126                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 127                 rpc_free_pdu(rpc, pdu);
 128                 return -1;
 129         }
 130
 131         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 132         SLIST_ADD_END(&rpc->outqueue, pdu);
 133
 134         return 0;
 135 }
 136
 137 int rpc_get_pdu_size(char *buf)
 138 {
 139         uint32_t size;
 140
 141         size = ntohl(*(uint32_t *)buf);
 142
 143         if ((size & 0x80000000) == 0) {
 144                 /* cant handle oncrpc fragments */
 145                 return -1;
 146         }
 147
 148         return (size & 0x7fffffff) + 4;
 149 }
 150
 151 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, XDR *xdr)
 152 {
 153         struct rpc_msg msg;
 154
 155         memset(&msg, 0, sizeof(struct rpc_msg));
 156         msg.acpted_rply.ar_verf = _null_auth;
 157         if (pdu->xdr_decode_bufsize > 0) {
 158                 if (pdu->xdr_decode_buf != NULL) {
 159                         free(pdu->xdr_decode_buf);
 160                 }
 161                 pdu->xdr_decode_buf = malloc(pdu->xdr_decode_bufsize);
 162                 if (pdu->xdr_decode_buf == NULL) {
 163                         rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 164                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate buffer for decoding of XDR reply", pdu->private_data);
 165                         return 0;
 166                 }
 167                 memset(pdu->xdr_decode_buf, 0, pdu->xdr_decode_bufsize);
 168         }
 169         msg.acpted_rply.ar_results.where = pdu->xdr_decode_buf;
 170         msg.acpted_rply.ar_results.proc  = pdu->xdr_decode_fn;
 171
 172         if (xdr_replymsg(xdr, &msg) == 0) {
 173                 rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 174                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server", pdu->private_data);
 175                 if (pdu->xdr_decode_buf != NULL) {
 176                         free(pdu->xdr_decode_buf);
 177                         pdu->xdr_decode_buf = NULL;
 178                 }
 179                 return 0;
 180         }
 181         if (msg.rm_reply.rp_stat != MSG_ACCEPTED) {
 182                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 183                 return 0;
 184         }
 185         switch (msg.rm_reply.rp_acpt.ar_stat) {
 186         case SUCCESS:
 187                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->xdr_decode_buf, pdu->private_data);
 188                 break;
 189         case PROG_UNAVAIL:
 190                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 191                 break;
 192         case PROG_MISMATCH:
 193                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 194                 break;
 195         case PROC_UNAVAIL:
 196                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 197                 break;
 198         case GARBAGE_ARGS:
 199                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 200                 break;
 201         case SYSTEM_ERR:
 202                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 203                 break;
 204         default:
 205                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 206                 break;
 207         }
 208
 209         return 0;
 210 }
 211
 212 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 213 {
 214         struct rpc_pdu *pdu;
 215         XDR xdr;
 216         int pos, recordmarker;
 217         unsigned int xid;
 218
 219         memset(&xdr, 0, sizeof(XDR));
 220
 221         xdrmem_create(&xdr, buf, size, XDR_DECODE);
 222         if (rpc->is_udp == 0) {
 223                 if (xdr_int(&xdr, &recordmarker) == 0) {
 224                         rpc_set_error(rpc, "xdr_int reading recordmarker failed");
 225                         xdr_destroy(&xdr);
 226                         return -1;
 227                 }
 228         }
 229         pos = xdr_getpos(&xdr);
 230         if (xdr_int(&xdr, (int *)&xid) == 0) {
 231                 rpc_set_error(rpc, "xdr_int reading xid failed");
 232                 xdr_destroy(&xdr);
 233                 return -1;
 234         }
 235         xdr_setpos(&xdr, pos);
 236
 237         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 238                 if (pdu->xid != xid) {
 239                         continue;
 240                 }
 241                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 242                         SLIST_REMOVE(&rpc->waitpdu, pdu);
 243                 }
 244                 if (rpc_process_reply(rpc, pdu, &xdr) != 0) {
 245                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 246                 }
 247                 xdr_destroy(&xdr);
 248                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 249                         rpc_free_pdu(rpc, pdu);
 250                 }
 251                 return 0;
 252         }
 253         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 254         xdr_destroy(&xdr);
 255         return -1;
 256 }
 257