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