| 1 | /* kern_prot.c 5.13 82/12/17 */ |
| 2 | |
| 3 | /* |
| 4 | * System calls related to processes and protection |
| 5 | */ |
| 6 | |
| 7 | #include "../machine/reg.h" |
| 8 | |
| 9 | #include "../h/param.h" |
| 10 | #include "../h/systm.h" |
| 11 | #include "../h/dir.h" |
| 12 | #include "../h/user.h" |
| 13 | #include "../h/inode.h" |
| 14 | #include "../h/proc.h" |
| 15 | #include "../h/timeb.h" |
| 16 | #include "../h/times.h" |
| 17 | #include "../h/reboot.h" |
| 18 | #include "../h/fs.h" |
| 19 | #include "../h/conf.h" |
| 20 | #include "../h/buf.h" |
| 21 | #include "../h/mount.h" |
| 22 | #include "../h/quota.h" |
| 23 | |
| 24 | getpid() |
| 25 | { |
| 26 | |
| 27 | u.u_r.r_val1 = u.u_procp->p_pid; |
| 28 | u.u_r.r_val2 = u.u_procp->p_ppid; |
| 29 | } |
| 30 | |
| 31 | getpgrp() |
| 32 | { |
| 33 | register struct a { |
| 34 | int pid; |
| 35 | } *uap = (struct a *)u.u_ap; |
| 36 | register struct proc *p; |
| 37 | |
| 38 | if (uap->pid == 0) |
| 39 | uap->pid = u.u_procp->p_pid; |
| 40 | p = pfind(uap->pid); |
| 41 | if (p == 0) { |
| 42 | u.u_error = ESRCH; |
| 43 | return; |
| 44 | } |
| 45 | u.u_r.r_val1 = p->p_pgrp; |
| 46 | } |
| 47 | |
| 48 | getuid() |
| 49 | { |
| 50 | |
| 51 | u.u_r.r_val1 = u.u_ruid; |
| 52 | u.u_r.r_val2 = u.u_uid; |
| 53 | } |
| 54 | |
| 55 | getgid() |
| 56 | { |
| 57 | |
| 58 | u.u_r.r_val1 = u.u_rgid; |
| 59 | u.u_r.r_val2 = u.u_gid; |
| 60 | } |
| 61 | |
| 62 | getgroups() |
| 63 | { |
| 64 | register struct a { |
| 65 | u_int gidsetsize; |
| 66 | int *gidset; |
| 67 | } *uap = (struct a *)u.u_ap; |
| 68 | register int *gp; |
| 69 | |
| 70 | for (gp = &u.u_groups[NGROUPS]; gp > u.u_groups; gp--) |
| 71 | if (gp[-1] >= 0) |
| 72 | break; |
| 73 | if (uap->gidsetsize < gp - u.u_groups) { |
| 74 | u.u_error = EINVAL; |
| 75 | return; |
| 76 | } |
| 77 | uap->gidsetsize = gp - u.u_groups; |
| 78 | if (copyout((caddr_t)u.u_groups, (caddr_t)uap->gidset, |
| 79 | uap->gidsetsize * sizeof (u.u_groups[0]))) { |
| 80 | u.u_error = EFAULT; |
| 81 | return; |
| 82 | } |
| 83 | u.u_r.r_val1 = uap->gidsetsize; |
| 84 | } |
| 85 | |
| 86 | setpgrp() |
| 87 | { |
| 88 | register struct proc *p; |
| 89 | register struct a { |
| 90 | int pid; |
| 91 | int pgrp; |
| 92 | } *uap = (struct a *)u.u_ap; |
| 93 | |
| 94 | if (uap->pid == 0) |
| 95 | uap->pid = u.u_procp->p_pid; |
| 96 | p = pfind(uap->pid); |
| 97 | if (p == 0) { |
| 98 | u.u_error = ESRCH; |
| 99 | return; |
| 100 | } |
| 101 | /* need better control mechanisms for process groups */ |
| 102 | if (p->p_uid != u.u_uid && u.u_uid && !inferior(p)) { |
| 103 | u.u_error = EPERM; |
| 104 | return; |
| 105 | } |
| 106 | p->p_pgrp = uap->pgrp; |
| 107 | } |
| 108 | |
| 109 | setreuid() |
| 110 | { |
| 111 | struct a { |
| 112 | int ruid; |
| 113 | int euid; |
| 114 | } *uap; |
| 115 | register int ruid, euid; |
| 116 | |
| 117 | uap = (struct a *)u.u_ap; |
| 118 | ruid = uap->ruid; |
| 119 | if (ruid == -1) |
| 120 | ruid = u.u_ruid; |
| 121 | if (u.u_ruid != ruid && u.u_uid != ruid && !suser()) |
| 122 | return; |
| 123 | euid = uap->euid; |
| 124 | if (euid == -1) |
| 125 | euid = u.u_uid; |
| 126 | if (u.u_ruid != euid && u.u_uid != euid && !suser()) |
| 127 | return; |
| 128 | /* |
| 129 | * Everything's okay, do it. |
| 130 | */ |
| 131 | #ifdef QUOTA |
| 132 | if (u.u_quota->q_uid != ruid) { |
| 133 | qclean(); |
| 134 | qstart(getquota(ruid, 0, 0)); |
| 135 | } |
| 136 | #endif |
| 137 | u.u_procp->p_uid = ruid; |
| 138 | u.u_ruid = ruid; |
| 139 | u.u_uid = euid; |
| 140 | } |
| 141 | |
| 142 | #ifndef NOCOMPAT |
| 143 | osetuid() |
| 144 | { |
| 145 | register uid; |
| 146 | register struct a { |
| 147 | int uid; |
| 148 | } *uap; |
| 149 | |
| 150 | uap = (struct a *)u.u_ap; |
| 151 | uid = uap->uid; |
| 152 | if (u.u_ruid == uid || u.u_uid == uid || suser()) { |
| 153 | #ifdef QUOTA |
| 154 | if (u.u_quota->q_uid != uid) { |
| 155 | qclean(); |
| 156 | qstart(getquota(uid, 0, 0)); |
| 157 | } |
| 158 | #endif |
| 159 | u.u_uid = uid; |
| 160 | u.u_procp->p_uid = uid; |
| 161 | u.u_ruid = uid; |
| 162 | } |
| 163 | } |
| 164 | #endif |
| 165 | |
| 166 | setregid() |
| 167 | { |
| 168 | register struct a { |
| 169 | int rgid; |
| 170 | int egid; |
| 171 | } *uap; |
| 172 | register int rgid, egid; |
| 173 | |
| 174 | uap = (struct a *)u.u_ap; |
| 175 | rgid = uap->rgid; |
| 176 | if (rgid == -1) |
| 177 | rgid = u.u_rgid; |
| 178 | if (u.u_rgid != rgid && u.u_gid != rgid && !suser()) |
| 179 | return; |
| 180 | egid = uap->egid; |
| 181 | if (egid == -1) |
| 182 | egid = u.u_gid; |
| 183 | if (u.u_rgid != egid && u.u_gid != egid && !suser()) |
| 184 | return; |
| 185 | if (u.u_rgid != rgid) { |
| 186 | leavegroup(u.u_rgid); |
| 187 | (void) entergroup(u.u_rgid); |
| 188 | u.u_rgid = rgid; |
| 189 | } |
| 190 | if (u.u_gid != egid) { |
| 191 | leavegroup(u.u_gid); |
| 192 | (void) entergroup(egid); |
| 193 | u.u_gid = egid; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | #ifndef NOCOMPAT |
| 198 | osetgid() |
| 199 | { |
| 200 | register gid; |
| 201 | register struct a { |
| 202 | int gid; |
| 203 | } *uap; |
| 204 | |
| 205 | uap = (struct a *)u.u_ap; |
| 206 | gid = uap->gid; |
| 207 | if (u.u_rgid == gid || u.u_gid == gid || suser()) { |
| 208 | leavegroup(u.u_gid); leavegroup(u.u_rgid); |
| 209 | (void) entergroup(gid); |
| 210 | u.u_gid = gid; |
| 211 | u.u_rgid = gid; |
| 212 | } |
| 213 | } |
| 214 | |
| 215 | setgroups() |
| 216 | { |
| 217 | register struct a { |
| 218 | u_int gidsetsize; |
| 219 | int *gidset; |
| 220 | } *uap = (struct a *)u.u_ap; |
| 221 | register int *gp; |
| 222 | |
| 223 | if (!suser()) |
| 224 | return; |
| 225 | if (uap->gidsetsize > sizeof (u.u_groups) / sizeof (u.u_groups[0])) { |
| 226 | u.u_error = EINVAL; |
| 227 | return; |
| 228 | } |
| 229 | if (copyin((caddr_t)uap->gidset, (caddr_t)u.u_groups, |
| 230 | uap->gidsetsize * sizeof (u.u_groups[0]))) { |
| 231 | u.u_error = EFAULT; |
| 232 | return; |
| 233 | } |
| 234 | for (gp = &u.u_groups[uap->gidsetsize]; gp < &u.u_groups[NGROUPS]; gp++) |
| 235 | *gp = -1; |
| 236 | } |
| 237 | |
| 238 | /* |
| 239 | * Pid of zero implies current process. |
| 240 | * Pgrp -1 is getpgrp system call returning |
| 241 | * current process group. |
| 242 | */ |
| 243 | osetpgrp() |
| 244 | { |
| 245 | register struct proc *p; |
| 246 | register struct a { |
| 247 | int pid; |
| 248 | int pgrp; |
| 249 | } *uap; |
| 250 | |
| 251 | uap = (struct a *)u.u_ap; |
| 252 | if (uap->pid == 0) |
| 253 | p = u.u_procp; |
| 254 | else { |
| 255 | p = pfind(uap->pid); |
| 256 | if (p == 0) { |
| 257 | u.u_error = ESRCH; |
| 258 | return; |
| 259 | } |
| 260 | } |
| 261 | if (uap->pgrp <= 0) { |
| 262 | u.u_r.r_val1 = p->p_pgrp; |
| 263 | return; |
| 264 | } |
| 265 | if (p->p_uid != u.u_uid && u.u_uid && !inferior(p)) { |
| 266 | u.u_error = EPERM; |
| 267 | return; |
| 268 | } |
| 269 | p->p_pgrp = uap->pgrp; |
| 270 | } |
| 271 | /* END DEFUNCT */ |
| 272 | |
| 273 | leavegroup(gid) |
| 274 | int gid; |
| 275 | { |
| 276 | register int *gp; |
| 277 | |
| 278 | for (gp = u.u_groups; gp < &u.u_groups[NGROUPS]; gp++) |
| 279 | if (*gp == gid) |
| 280 | goto found; |
| 281 | return; |
| 282 | found: |
| 283 | for (; gp < &u.u_groups[NGROUPS-1]; gp++) |
| 284 | *gp = *(gp+1); |
| 285 | *gp = -1; |
| 286 | } |
| 287 | |
| 288 | entergroup(gid) |
| 289 | int gid; |
| 290 | { |
| 291 | register int *gp; |
| 292 | |
| 293 | for (gp = u.u_groups; gp < &u.u_groups[NGROUPS]; gp++) |
| 294 | if (*gp == gid) |
| 295 | return (0); |
| 296 | for (gp = u.u_groups; gp < &u.u_groups[NGROUPS]; gp++) |
| 297 | if (*gp < 0) { |
| 298 | *gp = gid; |
| 299 | return (0); |
| 300 | } |
| 301 | return (-1); |
| 302 | } |