src/cokebank_basic/bank.c

   1 /*
   2  * OpenDispense 2
   3  * UCC (University [of WA] Computer Club) Electronic Accounting System
   4  * - Cokebank (Basic Version)
   5  *
   6  * bank.c - Actual bank database
   7  *
   8  * This file is licenced under the 3-clause BSD Licence. See the file COPYING
   9  * for full details.
  10  */
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <limits.h>
  15 #include <pwd.h>
  16 #include <grp.h>
  17 #include "common.h"
  18
  19 #define USE_UNIX_GROUPS 1
  20
  21 // === PROTOTYPES ===
  22 static int      GetUnixID(const char *Username);
  23
  24 // === GLOBALS ===
  25 tUser   *gaBank_Users;
  26  int    giBank_NumUsers;
  27 FILE    *gBank_File;
  28
  29 // === CODE ===
  30 int Bank_GetUserByName(const char *Username)
  31 {
  32          int    i, uid;
  33
  34         uid = GetUnixID(Username);
  35
  36         // Expensive search :(
  37         for( i = 0; i < giBank_NumUsers; i ++ )
  38         {
  39                 if( gaBank_Users[i].UnixID == uid )
  40                         return i;
  41         }
  42
  43         return -1;
  44 }
  45
  46 int Bank_GetUserBalance(int ID)
  47 {
  48         if( ID < 0 || ID >= giBank_NumUsers )
  49                 return INT_MIN;
  50
  51         return gaBank_Users[ID].Balance;
  52 }
  53
  54 int Bank_GetUserFlags(int ID)
  55 {
  56         if( ID < 0 || ID >= giBank_NumUsers )
  57                 return -1;
  58
  59         // TODO: Implement checking the PAM groups and status instead, then
  60         // fall back on the database. (and update if there is a difference)
  61
  62         // root
  63         if( gaBank_Users[ID].UnixID == 0 ) {
  64                 gaBank_Users[ID].Flags &= ~USER_FLAG_TYPEMASK;
  65                 gaBank_Users[ID].Flags |= USER_TYPE_WHEEL;
  66         }
  67
  68         #if USE_UNIX_GROUPS
  69         if( gaBank_Users[ID].UnixID > 0 )
  70         {
  71                 struct passwd   *pwd;
  72                 struct group    *grp;
  73                  int    i;
  74
  75                 // Get username
  76                 pwd = getpwuid( gaBank_Users[ID].UnixID );
  77
  78                 // Check for additions to the "coke" group
  79                 grp = getgrnam("coke");
  80                 if( grp ) {
  81                         for( i = 0; grp->gr_mem[i]; i ++ )
  82                         {
  83                                 if( strcmp(grp->gr_mem[i], pwd->pw_name) == 0 )
  84                                 {
  85                                         gaBank_Users[ID].Flags &= ~USER_FLAG_TYPEMASK;
  86                                         gaBank_Users[ID].Flags |= USER_TYPE_COKE;
  87                                 }
  88                         }
  89                 }
  90
  91                 // Check for additions to the "wheel" group
  92                 grp = getgrnam("wheel");
  93                 if( grp ) {
  94                         for( i = 0; grp->gr_mem[i]; i ++ )
  95                         {
  96                                 if( strcmp(grp->gr_mem[i], pwd->pw_name) == 0 )
  97                                 {
  98                                         gaBank_Users[ID].Flags &= ~USER_FLAG_TYPEMASK;
  99                                         gaBank_Users[ID].Flags |= USER_TYPE_WHEEL;
 100                                 }
 101                         }
 102                 }
 103         }
 104         #endif
 105
 106         return gaBank_Users[ID].Flags;
 107 }
 108
 109 int Bank_AlterUserBalance(int ID, int Delta)
 110 {
 111         // Sanity
 112         if( ID < 0 || ID >= giBank_NumUsers )
 113                 return -1;
 114
 115         // Update
 116         gaBank_Users[ID].Balance += Delta;
 117
 118         // Commit
 119         fseek(gBank_File, ID*sizeof(gaBank_Users[0]), SEEK_SET);
 120         fwrite(&gaBank_Users[ID], sizeof(gaBank_Users[0]), 1, gBank_File);
 121
 122         return 0;
 123 }
 124
 125 int Bank_SetUserBalance(int ID, int Value)
 126 {
 127         // Sanity
 128         if( ID < 0 || ID >= giBank_NumUsers )
 129                 return -1;
 130
 131         // Update
 132         gaBank_Users[ID].Balance = Value;
 133
 134         // Commit
 135         fseek(gBank_File, ID*sizeof(gaBank_Users[0]), SEEK_SET);
 136         fwrite(&gaBank_Users[ID], sizeof(gaBank_Users[0]), 1, gBank_File);
 137
 138         return 0;
 139 }
 140
 141 int Bank_GetMinAllowedBalance(int ID)
 142 {
 143         if( ID < 0 || ID >= giBank_NumUsers )
 144                 return 0;
 145
 146         switch( Bank_GetUserFlags(ID) & USER_FLAG_TYPEMASK )
 147         {
 148         case USER_TYPE_NORMAL:  return      0;
 149         case USER_TYPE_COKE:    return  -2000;
 150         case USER_TYPE_WHEEL:   return -10000;
 151         case USER_TYPE_GOD:     return INT_MIN;
 152         default:        return 0;
 153         }
 154 }
 155
 156 /**
 157  * \brief Create a new user in our database
 158  */
 159 int Bank_AddUser(const char *Username)
 160 {
 161         void    *tmp;
 162          int    uid = GetUnixID(Username);
 163
 164         // Can has moar space plz?
 165         tmp = realloc(gaBank_Users, (giBank_NumUsers+1)*sizeof(gaBank_Users[0]));
 166         if( !tmp )      return -1;
 167         gaBank_Users = tmp;
 168
 169         // Crete new user
 170         gaBank_Users[giBank_NumUsers].UnixID = uid;
 171         gaBank_Users[giBank_NumUsers].Balance = 0;
 172         gaBank_Users[giBank_NumUsers].Flags = 0;
 173
 174         if( strcmp(Username, COKEBANK_DEBT_ACCT) == 0 ) {
 175                 gaBank_Users[giBank_NumUsers].Flags = USER_TYPE_GOD;    // No minium
 176         }
 177         else if( strcmp(Username, "root") == 0 ) {
 178                 gaBank_Users[giBank_NumUsers].Flags = USER_TYPE_GOD;    // No minium
 179         }
 180
 181         // Commit to file
 182         fseek(gBank_File, giBank_NumUsers*sizeof(gaBank_Users[0]), SEEK_SET);
 183         fwrite(&gaBank_Users[giBank_NumUsers], sizeof(gaBank_Users[0]), 1, gBank_File);
 184
 185         // Increment count
 186         giBank_NumUsers ++;
 187
 188         return 0;
 189 }
 190
 191 // ---
 192 // Unix user dependent code
 193 // TODO: Modify to keep its own list of usernames
 194 // ---
 195 char *Bank_GetUserName(int ID)
 196 {
 197         struct passwd   *pwd;
 198
 199         if( ID < 0 || ID >= giBank_NumUsers )
 200                 return NULL;
 201
 202         if( gaBank_Users[ID].UnixID == -1 )
 203                 return strdup(COKEBANK_SALES_ACCT);
 204
 205         if( gaBank_Users[ID].UnixID == -2 )
 206                 return strdup(COKEBANK_DEBT_ACCT);
 207
 208         pwd = getpwuid(gaBank_Users[ID].UnixID);
 209         if( !pwd )      return NULL;
 210
 211         return strdup(pwd->pw_name);
 212 }
 213
 214 static int GetUnixID(const char *Username)
 215 {
 216          int    uid;
 217
 218         if( strcmp(Username, COKEBANK_SALES_ACCT) == 0 ) {      // Pseudo account that sales are made into
 219                 uid = -1;
 220         }
 221         else if( strcmp(Username, COKEBANK_DEBT_ACCT) == 0 ) {  // Pseudo acount that money is added from
 222                 uid = -2;
 223         }
 224         else {
 225                 struct passwd   *pwd;
 226                 // Get user ID
 227                 pwd = getpwnam(Username);
 228                 if( !pwd )      return -1;
 229                 uid = pwd->pw_uid;
 230         }
 231         return uid;
 232 }