| 1 | /* |
| 2 | * This file is part of DisOrder |
| 3 | * Copyright (C) 2005, 2007, 2008 Richard Kettlewell |
| 4 | * |
| 5 | * This program is free software: you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation, either version 3 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | /** @file clients/authorize.c |
| 19 | * @brief Create a new login |
| 20 | */ |
| 21 | |
| 22 | #include "common.h" |
| 23 | |
| 24 | #include <pwd.h> |
| 25 | #include <gcrypt.h> |
| 26 | #include <errno.h> |
| 27 | #include <unistd.h> |
| 28 | #include <sys/stat.h> |
| 29 | #include <fcntl.h> |
| 30 | |
| 31 | #include "client.h" |
| 32 | #include "authorize.h" |
| 33 | #include "log.h" |
| 34 | #include "configuration.h" |
| 35 | #include "printf.h" |
| 36 | #include "base64.h" |
| 37 | |
| 38 | /** @brief Create a DisOrder login for the calling user, called @p user |
| 39 | * @param client DisOrder client |
| 40 | * @param user Username to create (UTF-8) |
| 41 | * @param rights Initial rights or NULL for default |
| 42 | * @return 0 on success, non-0 on error |
| 43 | */ |
| 44 | int authorize(disorder_client *client, const char *user, const char *rights) { |
| 45 | /* base64 is 3-into-4 so we make the password a multiple of 3 bytes long */ |
| 46 | uint8_t pwbin[12]; |
| 47 | const struct passwd *pw; |
| 48 | char *pwhex; |
| 49 | int fd; |
| 50 | FILE *fp; |
| 51 | char *configdir, *configpath, *configpathtmp; |
| 52 | struct stat sb; |
| 53 | uid_t old_uid = getuid(); |
| 54 | gid_t old_gid = getgid(); |
| 55 | |
| 56 | if(!(pw = getpwnam(user))) |
| 57 | /* If it's a NIS world then /etc/passwd may be a lie, but it emphasizes |
| 58 | * that it's talking about the login user, not the DisOrder user */ |
| 59 | disorder_fatal(0, "no such user as %s in /etc/passwd", user); |
| 60 | |
| 61 | /* Choose a random password */ |
| 62 | gcry_randomize(pwbin, sizeof pwbin, GCRY_STRONG_RANDOM); |
| 63 | pwhex = mime_to_base64(pwbin, sizeof pwbin); |
| 64 | |
| 65 | /* Create the user on the server */ |
| 66 | if(disorder_adduser(client, user, pwhex, rights)) |
| 67 | return -1; |
| 68 | |
| 69 | /* Become the target user */ |
| 70 | if(setegid(pw->pw_gid) < 0) |
| 71 | disorder_fatal(errno, "setegid %lu", (unsigned long)pw->pw_gid); |
| 72 | if(seteuid(pw->pw_uid) < 0) |
| 73 | disorder_fatal(errno, "seteuid %lu", (unsigned long)pw->pw_uid); |
| 74 | |
| 75 | /* Make sure the configuration directory exists*/ |
| 76 | byte_xasprintf(&configdir, "%s/.disorder", pw->pw_dir); |
| 77 | if(mkdir(configdir, 02700) < 0) { |
| 78 | if(errno != EEXIST) |
| 79 | disorder_fatal(errno, "creating %s", configdir); |
| 80 | } |
| 81 | |
| 82 | /* Make sure the configuration file does not exist */ |
| 83 | byte_xasprintf(&configpath, "%s/passwd", configdir); |
| 84 | if(lstat(configpath, &sb) == 0) |
| 85 | disorder_fatal(0, "%s already exists", configpath); |
| 86 | if(errno != ENOENT) |
| 87 | disorder_fatal(errno, " checking %s", configpath); |
| 88 | |
| 89 | byte_xasprintf(&configpathtmp, "%s.new", configpath); |
| 90 | |
| 91 | /* Create config file with mode 600 */ |
| 92 | if((fd = open(configpathtmp, O_WRONLY|O_CREAT, 0600)) < 0) |
| 93 | disorder_fatal(errno, "error creating %s", configpathtmp); |
| 94 | |
| 95 | /* Write password */ |
| 96 | if(!(fp = fdopen(fd, "w"))) |
| 97 | disorder_fatal(errno, "error calling fdopen"); |
| 98 | if(fprintf(fp, "password %s\n", pwhex) < 0 |
| 99 | || fclose(fp) < 0) |
| 100 | disorder_fatal(errno, "error writing to %s", configpathtmp); |
| 101 | |
| 102 | /* Rename config file into place */ |
| 103 | if(rename(configpathtmp, configpath) < 0) |
| 104 | disorder_fatal(errno, "error renaming %s to %s", configpathtmp, configpath); |
| 105 | |
| 106 | /* Put our identity back */ |
| 107 | if(seteuid(old_uid) < 0) |
| 108 | disorder_fatal(errno, "seteuid %lu", (unsigned long)old_uid); |
| 109 | if(setegid(old_gid) < 0) |
| 110 | disorder_fatal(errno, "setegid %lu", (unsigned long)old_gid); |
| 111 | |
| 112 | return 0; |
| 113 | } |
| 114 | |
| 115 | /* |
| 116 | Local Variables: |
| 117 | c-basic-offset:2 |
| 118 | comment-column:40 |
| 119 | fill-column:79 |
| 120 | indent-tabs-mode:nil |
| 121 | End: |
| 122 | */ |