helpers/basic_auth/MSNT/confload.cc

   1
   2 /*
   3  * confload.c
   4  * (C) 2000 Antonino Iannella, Stellar-X Pty Ltd
   5  * Released under GPL, see COPYING-2.0 for details.
   6  *
   7  * These routines load the msntauth configuration file.
   8  * It stores the servers to query, sets the denied and
   9  * allowed user files, and provides the
  10  * authenticating function.
  11  */
  12
  13 /* Squid provides a number of portability overrides */
  14 #include "config.h"
  15
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #include <syslog.h>
  20 #include <errno.h>
  21 #include <sys/param.h>
  22 #include <netdb.h>
  23 #include <assert.h>
  24
  25 #include "msntauth.h"
  26 #include "valid.h"
  27
  28 /* Path to configuration file */
  29 #ifndef SYSCONFDIR
  30 #define SYSCONFDIR "/usr/local/squid/etc"
  31 #endif
  32 #define CONFIGFILE   SYSCONFDIR "/msntauth.conf"
  33
  34 /* Maximum number of servers to query. This number can be increased. */
  35 #define MAXSERVERS 5
  36 #define NTHOSTLEN 65
  37
  38 extern char Denyuserpath[MAXPATHLEN];   /* MAXPATHLEN defined in param.h */
  39 extern char Allowuserpath[MAXPATHLEN];
  40
  41 typedef struct _ServerTuple {
  42     char pdc[NTHOSTLEN];
  43     char bdc[NTHOSTLEN];
  44     char domain[NTHOSTLEN];
  45 } ServerTuple;
  46
  47 ServerTuple ServerArray[MAXSERVERS];    /* Array of servers to query */
  48 int Serversqueried = 0;         /* Number of servers queried */
  49
  50 /* Declarations */
  51
  52 static void ProcessLine(char *);
  53 static void AddServer(char *, char *, char *);
  54 static int QueryServerForUser(int, char *, char *);
  55
  56 /*
  57  * Opens and reads the configuration file.
  58  * Returns 0 on success, or 1 for error.
  59  */
  60
  61 int
  62 OpenConfigFile(void)
  63 {
  64     FILE *ConfigFile;
  65     char Confbuf[2049];         /* Line reading buffer */
  66
  67     /* Initialise defaults */
  68
  69     Serversqueried = 0;
  70     memset(ServerArray, '\0', sizeof(ServerArray));
  71     memset(Denyuserpath, '\0', MAXPATHLEN);
  72     memset(Allowuserpath, '\0', MAXPATHLEN);
  73
  74     /* Open file */
  75     if ((ConfigFile = fopen(CONFIGFILE, "r")) == NULL) {
  76         syslog(LOG_ERR, "OpenConfigFile: Failed to open %s.", CONFIGFILE);
  77         syslog(LOG_ERR, "%s", strerror(errno));
  78         return 1;
  79     }
  80     /* Read in, one line at a time */
  81     while (!feof(ConfigFile)) {
  82         Confbuf[0] = '\0';
  83         if (NULL == fgets(Confbuf, 2048, ConfigFile))
  84             break;
  85         Confbuf[2048] = '\0';
  86         ProcessLine(Confbuf);
  87     }
  88
  89     /*
  90      * Check that at least one server is being queried. Report error if not.
  91      * Denied and allowed user files are hardcoded, so it's fine if they're
  92      * not set in the confugration file.
  93      */
  94     if (Serversqueried == 0) {
  95         syslog(LOG_ERR, "OpenConfigFile: No servers set in %s. At least one is needed.", CONFIGFILE);
  96         return 1;
  97     }
  98     fclose(ConfigFile);
  99     return 0;
 100 }
 101
 102 /* Parses a configuration file line. */
 103
 104 static void
 105 ProcessLine(char *Linebuf)
 106 {
 107     char *Directive;
 108     char *Param1;
 109     char *Param2;
 110     char *Param3;
 111
 112     /* Ignore empty lines */
 113     if (strlen(Linebuf) == 0)
 114         return;
 115
 116     /* Break up on whitespaces */
 117     if ((Directive = strtok(Linebuf, " \t\n")) == NULL)
 118         return;
 119
 120     /* Check for a comment line. If found, stop . */
 121     if (Directive[0] == '#')
 122         return;
 123
 124     /* Check for server line. Check for 3 parameters. */
 125     if (strcasecmp(Directive, "server") == 0) {
 126         Param1 = strtok(NULL, " \t\n");
 127         if (NULL == Param1) {
 128             syslog(LOG_ERR, "ProcessLine: 'server' missing PDC parameter.");
 129             return;
 130         }
 131         Param2 = strtok(NULL, " \t\n");
 132         if (NULL == Param2) {
 133             syslog(LOG_ERR, "ProcessLine: 'server' missing BDC parameter.");
 134             return;
 135         }
 136         Param3 = strtok(NULL, " \t\n");
 137         if (NULL == Param3) {
 138             syslog(LOG_ERR, "ProcessLine: 'server' missing domain parameter.");
 139             return;
 140         }
 141         AddServer(Param1, Param2, Param3);
 142         return;
 143     }
 144     /* Check for denyusers line */
 145     if (strcasecmp(Directive, "denyusers") == 0) {
 146         Param1 = strtok(NULL, " \t\n");
 147
 148         if (NULL == Param1) {
 149             syslog(LOG_ERR, "ProcessLine: A 'denyusers' line needs a filename parameter.");
 150             return;
 151         }
 152         memset(Denyuserpath, '\0', MAXPATHLEN);
 153         strncpy(Denyuserpath, Param1, MAXPATHLEN - 1);
 154         return;
 155     }
 156     /* Check for allowusers line */
 157     if (strcasecmp(Directive, "allowusers") == 0) {
 158         Param1 = strtok(NULL, " \t\n");
 159
 160         if (NULL == Param1) {
 161             syslog(LOG_ERR, "ProcessLine: An 'allowusers' line needs a filename parameter.");
 162             return;
 163         }
 164         memset(Allowuserpath, '\0', MAXPATHLEN);
 165         strncpy(Allowuserpath, Param1, MAXPATHLEN - 1);
 166         return;
 167     }
 168     /* Reports error for unknown line */
 169     syslog(LOG_ERR, "ProcessLine: Ignoring '%s' line.", Directive);
 170 }
 171
 172 /*
 173  * Adds a server to query to the server array.
 174  * Checks if the server IP is resolvable.
 175  * Checks if the number of servers to query is not exceeded.
 176  * Does not allow parameters longer than NTHOSTLEN.
 177  */
 178
 179 void
 180 AddServer(char *ParamPDC, char *ParamBDC, char *ParamDomain)
 181 {
 182     if (Serversqueried == MAXSERVERS) {
 183         syslog(LOG_ERR, "AddServer: Ignoring '%s' server line; "
 184                "too many servers.", ParamPDC);
 185         return;
 186     }
 187     if (gethostbyname(ParamPDC) == NULL) {
 188         syslog(LOG_ERR, "AddServer: Ignoring host '%s'. "
 189                "Cannot resolve its address.", ParamPDC);
 190         return;
 191     }
 192     if (gethostbyname(ParamBDC) == NULL) {
 193         syslog(LOG_USER | LOG_ERR, "AddServer: Ignoring host '%s'. "
 194                "Cannot resolve its address.", ParamBDC);
 195         return;
 196     }
 197     /* NOTE: ServerArray is zeroed in OpenConfigFile() */
 198     assert(Serversqueried < MAXSERVERS);
 199     strncpy(ServerArray[Serversqueried].pdc, ParamPDC, NTHOSTLEN - 1);
 200     strncpy(ServerArray[Serversqueried].bdc, ParamBDC, NTHOSTLEN - 1);
 201     strncpy(ServerArray[Serversqueried].domain, ParamDomain, NTHOSTLEN - 1);
 202     Serversqueried++;
 203 }
 204
 205 /*
 206  * Cycles through all servers to query.
 207  * Returns 0 if one server could authenticate the user.
 208  * Returns 1 if no server authenticated the user.
 209  */
 210
 211 int
 212 QueryServers(char *username, char *password)
 213 {
 214     int i;
 215     for (i = 0; i < Serversqueried; i++) {
 216         if (0 == QueryServerForUser(i, username, password))
 217             return 0;
 218     }
 219     return 1;
 220 }
 221
 222 /*
 223  * Attempts to authenticate the user with one server.
 224  * Logs syslog messages for different errors.
 225  * Returns 0 on success, non-zero on failure.
 226  */
 227
 228 /* Define for systems which don't support it, like Solaris */
 229 #ifndef LOG_AUTHPRIV
 230 #define LOG_AUTHPRIV LOG_AUTH
 231 #endif
 232
 233 static int
 234 QueryServerForUser(int x, char *username, char *password)
 235 {
 236     int result = 1;
 237
 238     result = Valid_User(username, password, ServerArray[x].pdc,
 239                         ServerArray[x].bdc, ServerArray[x].domain);
 240
 241     switch (result) {           /* Write any helpful syslog messages */
 242     case 0:
 243         break;
 244     case 1:
 245         syslog(LOG_AUTHPRIV | LOG_INFO, "Server error when checking %s.",
 246                username);
 247         break;
 248     case 2:
 249         syslog(LOG_AUTHPRIV | LOG_INFO, "Protocol error when checking %s.",
 250                username);
 251         break;
 252     case 3:
 253         syslog(LOG_AUTHPRIV | LOG_INFO, "Authentication failed for %s.",
 254                username);
 255         break;
 256     }
 257
 258     return result;
 259 }
 260
 261 /* Valid_User return codes -
 262  *
 263  * 0 - User authenticated successfully.
 264  * 1 - Server error.
 265  * 2 - Protocol error.
 266  * 3 - Logon error; Incorrect password or username given.
 267  */