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 #ifdef WIN32
  18 #include "win32_compat.h"
  19 #ifndef MSG_DONTWAIT
  20 #define MSG_DONTWAIT 0
  21 #endif
  22 #else
  23 #include <strings.h>
  24 #endif/*WIN32*/
  25
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include <errno.h>
  29 #include <rpc/rpc.h>
  30 #include <rpc/xdr.h>
  31 #include <rpc/rpc_msg.h>
  32 #include "slist.h"
  33 #include "libnfs.h"
  34 #include "libnfs-raw.h"
  35 #include "libnfs-private.h"
  36
  37 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)
  38 {
  39         struct rpc_pdu *pdu;
  40         struct rpc_msg msg;
  41
  42         if (rpc == NULL) {
  43                 return NULL;
  44         }
  45
  46         pdu = malloc(sizeof(struct rpc_pdu));
  47         if (pdu == NULL) {
  48                 rpc_set_error(rpc, "Out of memory: Failed to allocate pdu structure");
  49                 return NULL;
  50         }
  51         memset(pdu, 0, sizeof(struct rpc_pdu));
  52         pdu->xid                = rpc->xid++;
  53         pdu->cb                 = cb;
  54         pdu->private_data       = private_data;
  55         pdu->xdr_decode_fn      = xdr_decode_fn;
  56         pdu->xdr_decode_bufsize = xdr_decode_bufsize;
  57
  58         xdrmem_create(&pdu->xdr, rpc->encodebuf, rpc->encodebuflen, XDR_ENCODE);
  59         if (rpc->is_udp == 0) {
  60                 xdr_setpos(&pdu->xdr, 4); /* skip past the record marker */
  61         }
  62
  63         memset(&msg, 0, sizeof(struct rpc_msg));
  64         msg.rm_xid = pdu->xid;
  65         msg.rm_direction = CALL;
  66         msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
  67         msg.rm_call.cb_prog = program;
  68         msg.rm_call.cb_vers = version;
  69         msg.rm_call.cb_proc = procedure;
  70         msg.rm_call.cb_cred = rpc->auth->ah_cred;
  71         msg.rm_call.cb_verf = rpc->auth->ah_verf;
  72
  73         if (xdr_callmsg(&pdu->xdr, &msg) == 0) {
  74                 rpc_set_error(rpc, "xdr_callmsg failed");
  75                 xdr_destroy(&pdu->xdr);
  76                 free(pdu);
  77                 return NULL;
  78         }
  79
  80         return pdu;
  81 }
  82
  83 void rpc_free_pdu(struct rpc_context *rpc _U_, struct rpc_pdu *pdu)
  84 {
  85         if (pdu->outdata.data != NULL) {
  86                 free(pdu->outdata.data);
  87                 pdu->outdata.data = NULL;
  88         }
  89
  90         if (pdu->xdr_decode_buf != NULL) {
  91                 xdr_free(pdu->xdr_decode_fn, pdu->xdr_decode_buf);
  92                 free(pdu->xdr_decode_buf);
  93                 pdu->xdr_decode_buf = NULL;
  94         }
  95
  96         xdr_destroy(&pdu->xdr);
  97
  98         free(pdu);
  99 }
 100
 101
 102 int rpc_queue_pdu(struct rpc_context *rpc, struct rpc_pdu *pdu)
 103 {
 104         int size, recordmarker;
 105
 106         size = xdr_getpos(&pdu->xdr);
 107
 108         /* for udp we dont queue, we just send it straight away */
 109         if (rpc->is_udp != 0) {
 110                 if (sendto(rpc->fd, rpc->encodebuf, size, MSG_DONTWAIT, rpc->udp_dest, sizeof(struct sockaddr_in)) < 0) {
 111                         rpc_set_error(rpc, "Sendto failed with errno %s", strerror(errno));
 112                         rpc_free_pdu(rpc, pdu);
 113                         return -1;
 114                 }
 115                 SLIST_ADD_END(&rpc->waitpdu, pdu);
 116                 return 0;
 117         }
 118
 119         /* write recordmarker */
 120         xdr_setpos(&pdu->xdr, 0);
 121         recordmarker = (size - 4) | 0x80000000;
 122         xdr_int(&pdu->xdr, &recordmarker);
 123
 124         pdu->outdata.size = size;
 125         pdu->outdata.data = malloc(pdu->outdata.size);
 126         if (pdu->outdata.data == NULL) {
 127                 rpc_set_error(rpc, "Out of memory. Failed to allocate buffer for pdu\n");
 128                 rpc_free_pdu(rpc, pdu);
 129                 return -1;
 130         }
 131
 132         memcpy(pdu->outdata.data, rpc->encodebuf, pdu->outdata.size);
 133         SLIST_ADD_END(&rpc->outqueue, pdu);
 134
 135         return 0;
 136 }
 137
 138 int rpc_get_pdu_size(char *buf)
 139 {
 140         uint32_t size;
 141
 142         size = ntohl(*(uint32_t *)buf);
 143
 144         if ((size & 0x80000000) == 0) {
 145                 /* cant handle oncrpc fragments */
 146                 return -1;
 147         }
 148
 149         return (size & 0x7fffffff) + 4;
 150 }
 151
 152 static int rpc_process_reply(struct rpc_context *rpc, struct rpc_pdu *pdu, XDR *xdr)
 153 {
 154         struct rpc_msg msg;
 155
 156         memset(&msg, 0, sizeof(struct rpc_msg));
 157         msg.acpted_rply.ar_verf = _null_auth;
 158         if (pdu->xdr_decode_bufsize > 0) {
 159                 if (pdu->xdr_decode_buf != NULL) {
 160                         free(pdu->xdr_decode_buf);
 161                 }
 162                 pdu->xdr_decode_buf = malloc(pdu->xdr_decode_bufsize);
 163                 if (pdu->xdr_decode_buf == NULL) {
 164                         rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 165                         pdu->cb(rpc, RPC_STATUS_ERROR, "Failed to allocate buffer for decoding of XDR reply", pdu->private_data);
 166                         return 0;
 167                 }
 168                 memset(pdu->xdr_decode_buf, 0, pdu->xdr_decode_bufsize);
 169         }
 170         msg.acpted_rply.ar_results.where = pdu->xdr_decode_buf;
 171         msg.acpted_rply.ar_results.proc  = pdu->xdr_decode_fn;
 172
 173         if (xdr_replymsg(xdr, &msg) == 0) {
 174                 rpc_set_error(rpc, "xdr_replymsg failed in portmap_getport_reply");
 175                 pdu->cb(rpc, RPC_STATUS_ERROR, "Message rejected by server", pdu->private_data);
 176                 if (pdu->xdr_decode_buf != NULL) {
 177                         free(pdu->xdr_decode_buf);
 178                         pdu->xdr_decode_buf = NULL;
 179                 }
 180                 return 0;
 181         }
 182         if (msg.rm_reply.rp_stat != MSG_ACCEPTED) {
 183                 pdu->cb(rpc, RPC_STATUS_ERROR, "RPC Packet not accepted by the server", pdu->private_data);
 184                 return 0;
 185         }
 186         switch (msg.rm_reply.rp_acpt.ar_stat) {
 187         case SUCCESS:
 188                 pdu->cb(rpc, RPC_STATUS_SUCCESS, pdu->xdr_decode_buf, pdu->private_data);
 189                 break;
 190         case PROG_UNAVAIL:
 191                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program not available", pdu->private_data);
 192                 break;
 193         case PROG_MISMATCH:
 194                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Program version mismatch", pdu->private_data);
 195                 break;
 196         case PROC_UNAVAIL:
 197                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Procedure not available", pdu->private_data);
 198                 break;
 199         case GARBAGE_ARGS:
 200                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: Garbage arguments", pdu->private_data);
 201                 break;
 202         case SYSTEM_ERR:
 203                 pdu->cb(rpc, RPC_STATUS_ERROR, "Server responded: System Error", pdu->private_data);
 204                 break;
 205         default:
 206                 pdu->cb(rpc, RPC_STATUS_ERROR, "Unknown rpc response from server", pdu->private_data);
 207                 break;
 208         }
 209
 210         return 0;
 211 }
 212
 213 int rpc_process_pdu(struct rpc_context *rpc, char *buf, int size)
 214 {
 215         struct rpc_pdu *pdu;
 216         XDR xdr;
 217         int pos, recordmarker;
 218         unsigned int xid;
 219
 220         memset(&xdr, 0, sizeof(XDR));
 221
 222         xdrmem_create(&xdr, buf, size, XDR_DECODE);
 223         if (rpc->is_udp == 0) {
 224                 if (xdr_int(&xdr, &recordmarker) == 0) {
 225                         rpc_set_error(rpc, "xdr_int reading recordmarker failed");
 226                         xdr_destroy(&xdr);
 227                         return -1;
 228                 }
 229         }
 230         pos = xdr_getpos(&xdr);
 231         if (xdr_int(&xdr, (int *)&xid) == 0) {
 232                 rpc_set_error(rpc, "xdr_int reading xid failed");
 233                 xdr_destroy(&xdr);
 234                 return -1;
 235         }
 236         xdr_setpos(&xdr, pos);
 237
 238         for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 239                 if (pdu->xid != xid) {
 240                         continue;
 241                 }
 242                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 243                         SLIST_REMOVE(&rpc->waitpdu, pdu);
 244                 }
 245                 if (rpc_process_reply(rpc, pdu, &xdr) != 0) {
 246                         rpc_set_error(rpc, "rpc_procdess_reply failed");
 247                 }
 248                 xdr_destroy(&xdr);
 249                 if (rpc->is_udp == 0 || rpc->is_broadcast == 0) {
 250                         rpc_free_pdu(rpc, pdu);
 251                 }
 252                 return 0;
 253         }
 254         rpc_set_error(rpc, "No matching pdu found for xid:%d", xid);
 255         xdr_destroy(&xdr);
 256         return -1;
 257 }
 258