1: #include "parms.h"
   2: #include "structs.h"
   3: 
   4: #ifdef  RCSIDENT
   5: static char rcsid[] = "$Header: perms.c,v 1.7.0.1 85/04/09 11:42:48 notes Rel $";
   6: #endif	RCSIDENT
   7: 
   8: /*
   9:  *	getperms - opens and reads the permission file to
  10:  *	determine the access rights for this user
  11:  *
  12:  *	Uses a struture similar to PLATO's. A list is scanned
  13:  *	until a match is found. The access rights at that point
  14:  *	are then awarded to the user. In the event that no
  15:  *	match is found, no access rights are granted.
  16:  *
  17:  *	Original Coding:	Ray Essick	December 1981
  18:  */
  19: #include    <grp.h>
  20: #include    <sys/param.h>               /* for groups */
  21: /*
  22:  *	Make sure that the name NGROUPS is defined.
  23:  *	pre-4.1a probably doesn't define either.
  24:  *	4.1a uses the NGRPS constant
  25:  *	4.2 uses the NGROUPS constant
  26:  *	We make sure that NGROUPS is defined and use that in the
  27:  *	generic portion of the routine. The emulation for V7, 4.1, 4.1a
  28:  *	and such use the NGRPS or whatever is appropriate.
  29:  */
  30: #if defined(NGRPS) && ! defined(NGROUPS)
  31: #define NGROUPS NGRPS                   /* name change! */
  32: #endif
  33: #ifndef     NGROUPS
  34: #define     NGROUPS     1           /* could be better */
  35: #endif		NGROUPS
  36: 
  37: static char *gnameptr[NGROUPS];             /* point to names */
  38: static int  ngroups = 0;                /* true if have gids */
  39: 
  40: getperms (io, sysflag, name)
  41: struct io_f *io;
  42: int     sysflag;                    /* true for remote system */
  43: char   *name;
  44: {
  45: 
  46:     register int    i;
  47:     FILE * acs, *fopen ();
  48:     struct group   *gr,
  49:                    *getgrgid ();
  50:     char    fn[WDLEN];
  51:     struct perm_f   entry;
  52:     int     hisperms;                   /* built up perms */
  53:     int     given;                  /* if assigned perms */
  54: 
  55:     if (sysflag == 0 && globuid == Notesuid)        /* "notes" omnipotent */
  56:     {
  57:     io -> access = READOK + RESPOK + WRITOK + DRCTOK;/* all */
  58: /*
  59:  *	should I just set it to -1 or something that turns on
  60:  *	all the bits?  or leave it with the defined bits only?
  61:  */
  62:     return;
  63:     }
  64: 
  65:     if (sysflag == 0 && ngroups == 0)
  66:     {
  67:     register int    i,
  68:                     j;              /* temp loop stuff */
  69:     int     gidset[NGROUPS];            /* hold gid list */
  70: 
  71:     ngroups = NGROUPS;              /* max allowed */
  72:     /*
  73: 	 * NOTE that the getgroups system call doesn't behave as
  74: 	 * documented in the 4.2 manual.  The manual says to call it
  75: 	 * ret=getgroups(&ngroups,&gidset) where ngroups is value-result.
  76: 	 * and ret is 0 on success.  Actual implementation works as below.
  77: 	 */
  78:     if ((ngroups = getgroups (ngroups, &gidset)) >= 0)/* worked */
  79:     {
  80:         for (i = 0, j = 0; i < ngroups; i++)    /* get names */
  81:         {
  82:         if ((gr = getgrgid (gidset[i])) == NULL)
  83:             continue;               /* bogus, skip it */
  84:         gnameptr[j++] = strsave (gr -> gr_name);/* save it */
  85:         }
  86:         ngroups = j;                /* save count */
  87:     }
  88:     }
  89:     io -> access = 0;                   /* default null */
  90:     hisperms = 0;                   /* set up mask */
  91:     given = 0;
  92: 
  93:     sprintf (fn, "%s/%s/%s", io -> basedir, io -> nf, ACCESS);
  94:     x ((acs = fopen (fn, "r")) == NULL, "getperms: no list");
  95:     while (fread (&entry, sizeof entry, 1, acs) == 1)
  96:     {
  97:     if ((sysflag != 0) && (entry.ptype != PERMSYSTEM))
  98:         continue;                   /* looking for systems */
  99:     if ((sysflag == 0) && (entry.ptype == PERMSYSTEM))
 100:         continue;                   /* users != systems */
 101: 
 102:     if (strcmp (entry.name, "Other") == 0)
 103:     {
 104:         if (!given)                 /* he hasn't matched */
 105:         hisperms = entry.perms;         /* give him these */
 106:         goto gotit;                 /* and exit ... */
 107:     }
 108:     switch (entry.ptype)
 109:     {
 110:         case PERMUSER:
 111:         if (strcmp (name, entry.name) == 0)
 112:         {
 113:             hisperms = entry.perms;
 114:             goto gotit;
 115:         }
 116:         break;
 117: 
 118:         case PERMGROUP:                 /* a group entry */
 119:         for (i = 0; i < ngroups; i++)       /* check all */
 120:             if (strcmp (entry.name, gnameptr[i]) == 0)
 121:             {
 122:             hisperms |= entry.perms;    /* OR them in */
 123:             given++;            /* mark as such */
 124:             break;
 125:             }
 126:         break;
 127: 
 128:         case PERMSYSTEM:
 129:         if (strcmp (name, entry.name) == 0)
 130:         {
 131:             hisperms = entry.perms;
 132:             given++;
 133:             goto gotit;
 134:         }
 135:         break;
 136: 
 137:         default:                    /* bad access list */
 138:         x (1, "getperms: bad list");
 139:     }
 140:     }
 141: gotit:
 142:     fclose (acs);                   /* close the access file */
 143:     io -> access = hisperms;                /* what we built */
 144: 
 145:     return;
 146: }
 147: 
 148: /*
 149:  *	Some compatibility routines to let us use the fancy 4.2 Bsd
 150:  *	getgroups() system call while running 4.1, 4.1a or V7 kernels.
 151:  *	I've undoubtedly missed some kernels.
 152:  */
 153: 
 154: 
 155: /*
 156:  *	getgroups
 157:  *
 158:  *	Returns an integer and a set of groups.
 159:  *	Emulates the 4.2 getgroups command under 4.1a Bsd
 160:  *
 161:  *	Stolen mostly from the 4.1a command "groups".
 162:  *
 163:  *	Ray Essick, January 1984
 164:  *
 165:  */
 166: 
 167: #if defined (BSD41A)
 168: 
 169: getgroups (ngroups, gidset)
 170: int     ngroups;
 171: int    *gidset;
 172: {
 173:     register int    i;
 174:     register int    maxback;                /* most to user */
 175:     int     grps[NGRPS / (sizeof (int) * 8)];       /* NGRPS=NGROUPS */
 176: 
 177:     setgrp (0, grps);                   /* get groups */
 178:     maxback = ngroups;                  /* save limit */
 179:     ngroups = 0;                    /* start empty */
 180:     for (i = 0; i < NGRPS && ngroups < maxback; i++)    /* for each */
 181:     if (grps[i / (sizeof (int) * 8)] & (1 << (i % (sizeof (int) * 8))))
 182:     {
 183:         *gidset++ = i;              /* save the group */
 184:         ngroups++;                  /* and count */
 185:     }
 186:     return (ngroups);
 187: }
 188: #endif	defined (BSD41A)
 189: 
 190: /*
 191:  *	The V7 and 4.1 version of this system call. Also serves well
 192:  *	for the 2.8 Bsd kernels and probably for the more recent BTL
 193:  *	kernels.
 194:  *	This could be extended to read from /etc/groups to actually give
 195:  *	the user all groups he is permitted.
 196:  */
 197: 
 198: #if defined (V7) || defined (BSD41) || defined (BSD2x) || defined (USG)
 199: getgroups (ngroups, gidset)             /* simple V7 one */
 200: int     ngroups;
 201: int    *gidset;
 202: {
 203:     *gidset = getgid () & GIDMASK;
 204:     ngroups = 1;
 205:     return (1);
 206: }
 207: #endif	defined (V7) || defined (BSD41) || defined (BSD2x) || defined(USG)

Defined functions

getgroups defined in line 199; used 1 times
  • in line 78

Defined variables

gnameptr defined in line 37; used 2 times
ngroups defined in line 38; used 17 times
rcsid defined in line 5; never used

Defined macros

NGROUPS defined in line 34; used 5 times
Last modified: 1985-10-30
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