src/user.c

   1 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2
   3 /*  Monkey HTTP Daemon
   4  *  ------------------
   5  *  Copyright (C) 2001-2002, Eduardo Silva P. <edsiper@gmail.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <pwd.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28 #include <sys/resource.h>
  29 #include <sys/types.h>
  30 #include <grp.h>
  31
  32 #include "monkey.h"
  33 #include "user.h"
  34 #include "http.h"
  35 #include "http_status.h"
  36 #include "memory.h"
  37 #include "str.h"
  38 #include "utils.h"
  39 #include "config.h"
  40
  41 int mk_user_init(struct client_request *cr, struct request *sr)
  42 {
  43     int limit;
  44     int offset = mk_user_home.len;
  45     char *user = 0, *user_server_root = 0;
  46     struct passwd *s_user;
  47     unsigned long len;
  48
  49     sr->user_home = VAR_ON;
  50
  51     user = mk_mem_malloc(strlen(sr->uri_processed) + 1);
  52     limit = mk_string_search(sr->uri_processed + offset, "/");
  53
  54     if (limit == -1)
  55         limit = strlen(sr->uri_processed) - offset;
  56
  57     strncpy(user, sr->uri_processed + offset, limit);
  58     user[limit] = '\0';
  59
  60     if (sr->uri.data[offset + limit] == '/') {
  61         mk_string_build(&sr->uri.data, &sr->uri.len,
  62                         "%s", sr->uri_processed + offset + limit);
  63
  64         /* Extract URI portion after /~user */
  65         sr->user_uri = (char *) mk_mem_malloc_z(sr->uri.len + 1);
  66         char *src = sr->uri.data;
  67         char *dst = sr->user_uri;
  68
  69         while (*src != ' ' && src < (sr->uri.data + sr->uri.len)) {
  70             *dst++ = *src++;
  71         }
  72     }
  73
  74     if ((s_user = getpwnam(user)) == NULL) {
  75         mk_mem_free(user);
  76         mk_request_error(M_CLIENT_NOT_FOUND, cr, sr, 1);
  77         return -1;
  78     }
  79     mk_mem_free(user);
  80
  81     mk_string_build(&user_server_root, &len, "%s/%s", s_user->pw_dir,
  82                     config->user_dir);
  83
  84     if (sr->user_uri != NULL) {
  85         mk_string_build(&sr->real_path.data, &sr->real_path.len, "%s%s",
  86                         user_server_root, sr->user_uri);
  87     }
  88     else {
  89         mk_string_build(&sr->real_path.data, &sr->real_path.len, "%s",
  90                         user_server_root);
  91     }
  92     mk_mem_free(user_server_root);
  93     return 0;
  94 }
  95
  96 /* Change process user */
  97 int mk_user_set_uidgid()
  98 {
  99     struct passwd *usr;
 100
 101     EGID = (gid_t) getegid();
 102     EUID = (gid_t) geteuid();
 103
 104     /* Launched by root ? */
 105     if (geteuid() == 0 && config->user) {
 106         struct rlimit rl;
 107
 108         /* Just if i'm superuser */
 109         rl.rlim_cur = rl.rlim_max;
 110         setrlimit(RLIMIT_NOFILE, &rl);
 111
 112         /* Check if user exists  */
 113         if ((usr = getpwnam(config->user)) == NULL) {
 114             printf("Error: Invalid user '%s'\n", config->user);
 115             exit(1);
 116         }
 117
 118
 119         if (initgroups(config->user, usr->pw_gid) != 0) {
 120             exit(1);
 121         }
 122
 123         /* Change process UID and GID */
 124         if (setgid(usr->pw_gid) == -1) {
 125             printf("I can't change the GID to %u\n", usr->pw_gid);
 126             exit(1);
 127         }
 128
 129
 130         if (setuid(usr->pw_uid) == -1) {
 131             printf("I can't change the UID to %u\n", usr->pw_uid);
 132             exit(1);
 133         }
 134
 135         EUID = geteuid();
 136         EGID = getegid();
 137     }
 138     return 0;
 139 }
 140
 141 /* Return process to the original user */
 142 int mk_user_undo_uidgid()
 143 {
 144     if (EUID == 0) {
 145         setegid(EGID);
 146         seteuid(EUID);
 147     }
 148     return 0;
 149 }