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 #include <stdio.h>
  19 #include <strings.h>
  20 #include <stdlib.h>
  21 #include <rpc/rpc.h>
  22 #include <rpc/xdr.h>
  23 #include <rpc/rpc_msg.h>
  24 #include "slist.h"
  25 #include "libnfs.h"
  26 #include "libnfs-raw.h"
  27 #include "libnfs-private.h"
  28
  29 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)
  30 {
  31         struct rpc_pdu *pdu;
  32         struct rpc_msg msg;
  33
  34         if (rpc == NULL) {
  35                 return NULL;
  36         }
  37
  38         pdu = malloc(sizeof(struct rpc_pdu));
  39         if (pdu == NULL) {
  40                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  41                 return NULL;
  42         }
  43         bzero(pdu, sizeof(struct rpc_pdu));
  44         pdu->xid                = rpc->xid++;
  45         pdu->cb                 = cb;
  46         pdu->private_data       = private_data;
  47         pdu->xdr_decode_fn      = xdr_decode_fn;
  48         pdu->xdr_decode_bufsize = xdr_decode_bufsize;
  49
  50         xdrmem_create(&pdu->xdr, rpc->encodebuf, rpc->encodebuflen, XDR_ENCODE);
  51         if (rpc->is_udp == 0) {
  52                 xdr_setpos(&pdu->xdr, 4); /* skip past the record marker */
  53         }
  54
  55         bzero(&msg, sizeof(struct rpc_msg));
  56         msg.rm_xid = pdu->xid;
  57         msg.rm_direction = CALL;
  58         msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
  59         msg.rm_call.cb_prog = program;
  60         msg.rm_call.cb_vers = version;
  61         msg.rm_call.cb_proc = procedure;
  62         msg.rm_call.cb_cred = rpc->auth->ah_cred;
  63         msg.rm_call.cb_verf = rpc->auth->ah_verf;
  64
  65         if (xdr_callmsg(&pdu->xdr, &msg) == 0) {
  66                 rpc_set_error(rpc, "xdr_callmsg failed");
  67                 xdr_destroy(&pdu->xdr);
  68                 free(pdu);
  69                 return NULL;
  70         }
  71
  72         return pdu;
  73 }
  74
  75 void rpc_free_pdu(struct rpc_context *rpc _U_, struct rpc_pdu *pdu)
  76 {
  77         if (pdu->outdata.data != NULL) {
  78                 free(pdu->outdata.data);
  79                 pdu->outdata.data = NULL;
  80         }
  81
  82         if (pdu->xdr_decode_buf != NULL) {
  83                 xdr_free(pdu->xdr_decode_fn, pdu->xdr_decode_buf);
  84                 free(pdu->xdr_decode_buf);
  85                 pdu->xdr_decode_buf = NULL;
  86         }
  87
  88         xdr_destroy(&pdu->xdr);
  89
  90         free(pdu);
  91 }
  92
  93
  94 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
  95 {
  96         int size, recordmarker;
  97
  98         size = xdr_getpos(&pdu->xdr);
  99
 100         /* write recordmarker */
 101         xdr_setpos(&pdu->xdr, 0);
 102         recordmarker = (size - 4) | 0x80000000;
 103         xdr_int(&pdu->xdr, &recordmarker);
 104
 105         pdu->outdata.size = size;
 106         pdu->outdata.data = malloc(pdu->outdata.size);
 107         if (pdu->outdata.data == NULL) {
 108                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 109                 rpc_free_pdu(rpc, pdu);
 110                 return -1;
 111         }
 112
 113         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 114         SLIST_ADD_END(&rpc->outqueue, pdu);
 115
 116         return 0;
 117 }
 118
 119 int rpc_get_pdu_size(char *buf)
 120 {
 121         uint32_t size;
 122
 123         size = ntohl(*(uint32_t *)buf);
 124
 125         if ((size & 0x80000000) == 0) {
 126                 /* cant handle oncrpc fragments */
 127                 return -1;
 128         }
 129
 130         return (size & 0x7fffffff) + 4;
 131 }
 132
 133 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, XDR *xdr)
 134 {
 135         struct rpc_msg msg;
 136
 137         bzero(&msg, sizeof(struct rpc_msg));
 138         msg.acpted_rply.ar_verf = _null_auth;
 139         if (pdu->xdr_decode_bufsize > 0) {
 140                 pdu->xdr_decode_buf = malloc(pdu->xdr_decode_bufsize);
 141                 if (pdu->xdr_decode_buf == NULL) {
 142                         rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 143                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate buffer for decoding of XDR reply", pdu->private_data);
 144                         return 0;
 145                 }
 146                 bzero(pdu->xdr_decode_buf, pdu->xdr_decode_bufsize);
 147         }
 148         msg.acpted_rply.ar_results.where = pdu->xdr_decode_buf;
 149         msg.acpted_rply.ar_results.proc  = pdu->xdr_decode_fn;
 150
 151         if (xdr_replymsg(xdr, &msg) == 0) {
 152                 rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 153                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server", pdu->private_data);
 154                 if (pdu->xdr_decode_buf != NULL) {
 155                         free(pdu->xdr_decode_buf);
 156                         pdu->xdr_decode_buf = NULL;
 157                 }
 158                 return 0;
 159         }
 160         if (msg.rm_reply.rp_stat != MSG_ACCEPTED) {
 161                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 162                 return 0;
 163         }
 164         switch (msg.rm_reply.rp_acpt.ar_stat) {
 165         case SUCCESS:
 166                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->xdr_decode_buf, pdu->private_data);
 167                 break;
 168         case PROG_UNAVAIL:
 169                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 170                 break;
 171         case PROG_MISMATCH:
 172                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 173                 break;
 174         case PROC_UNAVAIL:
 175                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 176                 break;
 177         case GARBAGE_ARGS:
 178                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 179                 break;
 180         case SYSTEM_ERR:
 181                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 182                 break;
 183         default:
 184                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 185                 break;
 186         }
 187
 188         return 0;
 189 }
 190
 191 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 192 {
 193         struct rpc_pdu *pdu;
 194         XDR xdr;
 195         int pos, recordmarker;
 196         unsigned int xid;
 197
 198         bzero(&xdr, sizeof(XDR));
 199
 200         xdrmem_create(&xdr, buf, size, XDR_DECODE);
 201         if (xdr_int(&xdr, &recordmarker) == 0) {
 202                 rpc_set_error(rpc, "xdr_int reading recordmarker failed");
 203                 xdr_destroy(&xdr);
 204                 return -1;
 205         }
 206         pos = xdr_getpos(&xdr);
 207         if (xdr_int(&xdr, (int *)&xid) == 0) {
 208                 rpc_set_error(rpc, "xdr_int reading xid failed");
 209                 xdr_destroy(&xdr);
 210                 return -1;
 211         }
 212         xdr_setpos(&xdr, pos);
 213
 214         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 215                 if (pdu->xid != xid) {
 216                         continue;
 217                 }
 218                 SLIST_REMOVE(&rpc->waitpdu, pdu);
 219                 if (rpc_process_reply(rpc, pdu, &xdr) != 0) {
 220                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 221                 }
 222                 xdr_destroy(&xdr);
 223                 rpc_free_pdu(rpc, pdu);
 224                 return 0;
 225         }
 226         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 227         xdr_destroy(&xdr);
 228         return -1;
 229 }
 230