src/ident/Ident.cc

   1 /*
   2  * DEBUG: section 30    Ident (RFC 931)
   3  * AUTHOR: Duane Wessels
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  */
  32 #include "squid.h"
  33
  34 #if USE_IDENT
  35 #include "comm.h"
  36 #include "comm/Connection.h"
  37 #include "comm/ConnOpener.h"
  38 #include "CommCalls.h"
  39 #include "comm/Write.h"
  40 #include "globals.h"
  41 #include "ident/Config.h"
  42 #include "ident/Ident.h"
  43 #include "MemBuf.h"
  44
  45 namespace Ident
  46 {
  47
  48 #define IDENT_PORT 113
  49 #define IDENT_KEY_SZ 50
  50 #define IDENT_BUFSIZE 4096
  51
  52 typedef struct _IdentClient {
  53     IDCB *callback;
  54     void *callback_data;
  55
  56     struct _IdentClient *next;
  57 } IdentClient;
  58
  59 typedef struct _IdentStateData {
  60     hash_link hash;             /* must be first */
  61     Comm::ConnectionPointer conn;
  62     MemBuf queryMsg;  ///< the lookup message sent to IDENT server
  63     IdentClient *clients;
  64     char buf[IDENT_BUFSIZE];
  65 } IdentStateData;
  66
  67 // TODO: make these all a series of Async job calls. They are self-contained callbacks now.
  68 static IOCB ReadReply;
  69 static IOCB WriteFeedback;
  70 static CLCB Close;
  71 static CTCB Timeout;
  72 static CNCB ConnectDone;
  73 static hash_table *ident_hash = NULL;
  74 static void ClientAdd(IdentStateData * state, IDCB * callback, void *callback_data);
  75 static void identCallback(IdentStateData * state, char *result);
  76
  77 } // namespace Ident
  78
  79 Ident::IdentConfig Ident::TheConfig;
  80
  81 /**** PRIVATE FUNCTIONS ****/
  82
  83 void
  84 Ident::identCallback(IdentStateData * state, char *result)
  85 {
  86     IdentClient *client;
  87
  88     if (result && *result == '\0')
  89         result = NULL;
  90
  91     while ((client = state->clients)) {
  92         void *cbdata;
  93         state->clients = client->next;
  94
  95         if (cbdataReferenceValidDone(client->callback_data, &cbdata))
  96             client->callback(result, cbdata);
  97
  98         xfree(client);
  99     }
 100 }
 101
 102 void
 103 Ident::Close(const CommCloseCbParams &params)
 104 {
 105     IdentStateData *state = (IdentStateData *)params.data;
 106     identCallback(state, NULL);
 107     state->conn->close();
 108     hash_remove_link(ident_hash, (hash_link *) state);
 109     xfree(state->hash.key);
 110     cbdataFree(state);
 111 }
 112
 113 void
 114 Ident::Timeout(const CommTimeoutCbParams &io)
 115 {
 116     debugs(30, 3, HERE << io.conn);
 117     io.conn->close();
 118 }
 119
 120 void
 121 Ident::ConnectDone(const Comm::ConnectionPointer &conn, comm_err_t status, int xerrno, void *data)
 122 {
 123     IdentStateData *state = (IdentStateData *)data;
 124
 125     if (status != COMM_OK) {
 126         if (status == COMM_TIMEOUT) {
 127             debugs(30, 3, "IDENT connection timeout to " << state->conn->remote);
 128         }
 129         return;
 130     }
 131
 132     assert(conn != NULL && conn == state->conn);
 133
 134     /*
 135      * see if any of our clients still care
 136      */
 137     IdentClient *c;
 138     for (c = state->clients; c; c = c->next) {
 139         if (cbdataReferenceValid(c->callback_data))
 140             break;
 141     }
 142
 143     if (c == NULL) {
 144         /* no clients care */
 145         conn->close();
 146         return;
 147     }
 148
 149     comm_add_close_handler(conn->fd, Ident::Close, state);
 150
 151     AsyncCall::Pointer writeCall = commCbCall(5,4, "Ident::WriteFeedback",
 152                                    CommIoCbPtrFun(Ident::WriteFeedback, state));
 153     Comm::Write(conn, &state->queryMsg, writeCall);
 154     AsyncCall::Pointer readCall = commCbCall(5,4, "Ident::ReadReply",
 155                                   CommIoCbPtrFun(Ident::ReadReply, state));
 156     comm_read(conn, state->buf, IDENT_BUFSIZE, readCall);
 157     AsyncCall::Pointer timeoutCall = commCbCall(5,4, "Ident::Timeout",
 158                                      CommTimeoutCbPtrFun(Ident::Timeout, state));
 159     commSetConnTimeout(conn, Ident::TheConfig.timeout, timeoutCall);
 160 }
 161
 162 void
 163 Ident::WriteFeedback(const Comm::ConnectionPointer &conn, char *buf, size_t len, comm_err_t flag, int xerrno, void *data)
 164 {
 165     debugs(30, 5, HERE << conn << ": Wrote IDENT request " << len << " bytes.");
 166
 167     // TODO handle write errors better. retry or abort?
 168     if (flag != COMM_OK) {
 169         debugs(30, 2, HERE << conn << " err-flags=" << flag << " IDENT write error: " << xstrerr(xerrno));
 170         conn->close();
 171     }
 172 }
 173
 174 void
 175 Ident::ReadReply(const Comm::ConnectionPointer &conn, char *buf, size_t len, comm_err_t flag, int xerrno, void *data)
 176 {
 177     IdentStateData *state = (IdentStateData *)data;
 178     char *ident = NULL;
 179     char *t = NULL;
 180
 181     assert(buf == state->buf);
 182     assert(conn->fd == state->conn->fd);
 183
 184     if (flag != COMM_OK || len <= 0) {
 185         state->conn->close();
 186         return;
 187     }
 188
 189     /*
 190      * XXX This isn't really very tolerant. It should read until EOL
 191      * or EOF and then decode the answer... If the reply is fragmented
 192      * then this will fail
 193      */
 194     buf[len] = '\0';
 195
 196     if ((t = strchr(buf, '\r')))
 197         *t = '\0';
 198
 199     if ((t = strchr(buf, '\n')))
 200         *t = '\0';
 201
 202     debugs(30, 5, HERE << conn << ": Read '" << buf << "'");
 203
 204     if (strstr(buf, "USERID")) {
 205         if ((ident = strrchr(buf, ':'))) {
 206             while (xisspace(*++ident));
 207             Ident::identCallback(state, ident);
 208         }
 209     }
 210
 211     state->conn->close();
 212 }
 213
 214 void
 215 Ident::ClientAdd(IdentStateData * state, IDCB * callback, void *callback_data)
 216 {
 217     IdentClient *c = (IdentClient *)xcalloc(1, sizeof(*c));
 218     IdentClient **C;
 219     c->callback = callback;
 220     c->callback_data = cbdataReference(callback_data);
 221
 222     for (C = &state->clients; *C; C = &(*C)->next);
 223     *C = c;
 224 }
 225
 226 CBDATA_TYPE(IdentStateData);
 227
 228 /**** PUBLIC FUNCTIONS ****/
 229
 230 /*
 231  * start a TCP connection to the peer host on port 113
 232  */
 233 void
 234 Ident::Start(const Comm::ConnectionPointer &conn, IDCB * callback, void *data)
 235 {
 236     IdentStateData *state;
 237     char key1[IDENT_KEY_SZ];
 238     char key2[IDENT_KEY_SZ];
 239     char key[IDENT_KEY_SZ];
 240
 241     conn->local.ToURL(key1, IDENT_KEY_SZ);
 242     conn->remote.ToURL(key2, IDENT_KEY_SZ);
 243     snprintf(key, IDENT_KEY_SZ, "%s,%s", key1, key2);
 244
 245     if (!ident_hash) {
 246         Init();
 247     }
 248     if ((state = (IdentStateData *)hash_lookup(ident_hash, key)) != NULL) {
 249         ClientAdd(state, callback, data);
 250         return;
 251     }
 252
 253     CBDATA_INIT_TYPE(IdentStateData);
 254     state = cbdataAlloc(IdentStateData);
 255     state->hash.key = xstrdup(key);
 256
 257     // copy the conn details. We dont want the original FD to be re-used by IDENT.
 258     state->conn = conn->copyDetails();
 259     // NP: use random port for secure outbound to IDENT_PORT
 260     state->conn->local.SetPort(0);
 261     state->conn->remote.SetPort(IDENT_PORT);
 262
 263     // build our query from the original connection details
 264     state->queryMsg.init();
 265     state->queryMsg.Printf("%d, %d\r\n", conn->remote.GetPort(), conn->local.GetPort());
 266
 267     ClientAdd(state, callback, data);
 268     hash_join(ident_hash, &state->hash);
 269
 270     AsyncCall::Pointer call = commCbCall(30,3, "Ident::ConnectDone", CommConnectCbPtrFun(Ident::ConnectDone, state));
 271     AsyncJob::Start(new Comm::ConnOpener(state->conn, call, Ident::TheConfig.timeout));
 272 }
 273
 274 void
 275 Ident::Init(void)
 276 {
 277     if (ident_hash) {
 278         debugs(30, DBG_CRITICAL, "WARNING: Ident already initialized.");
 279         return;
 280     }
 281
 282     ident_hash = hash_create((HASHCMP *) strcmp,
 283                              hashPrime(Squid_MaxFD / 8),
 284                              hash4);
 285 }
 286
 287 #endif /* USE_IDENT */