| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Utilities for the client and the server |
| 4 | * |
| 5 | * (c) 2001 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Trivial IP Encryption (TrIPE). |
| 11 | * |
| 12 | * TrIPE is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later version. |
| 16 | * |
| 17 | * TrIPE is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU General Public License |
| 23 | * along with TrIPE; if not, write to the Free Software Foundation, |
| 24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 25 | */ |
| 26 | |
| 27 | /*----- Header files ------------------------------------------------------*/ |
| 28 | |
| 29 | #include <errno.h> |
| 30 | #include <stdio.h> |
| 31 | #include <stdlib.h> |
| 32 | #include <string.h> |
| 33 | |
| 34 | #include <sys/types.h> |
| 35 | #include <unistd.h> |
| 36 | |
| 37 | #include <pwd.h> |
| 38 | #include <grp.h> |
| 39 | |
| 40 | #include <mLib/dstr.h> |
| 41 | #include <mLib/report.h> |
| 42 | |
| 43 | #include "util.h" |
| 44 | |
| 45 | /*----- Main code ---------------------------------------------------------*/ |
| 46 | |
| 47 | /* --- @u_quotify@ --- * |
| 48 | * |
| 49 | * Arguments: @dstr *d@ = where to write the answer |
| 50 | * @const char *p@ = string to quotify |
| 51 | * |
| 52 | * Returns: --- |
| 53 | * |
| 54 | * Use: Quotes the given string if necessary, according to our |
| 55 | * quoting rules. |
| 56 | */ |
| 57 | |
| 58 | void u_quotify(dstr *d, const char *p) |
| 59 | { |
| 60 | if (d->len) |
| 61 | dstr_putc(d, ' '); |
| 62 | if (*p && !p[strcspn(p, "\"' \t\n\v")]) |
| 63 | dstr_puts(d, p); |
| 64 | else { |
| 65 | dstr_putc(d, '\"'); |
| 66 | while (*p) { |
| 67 | if (*p == '\\' || *p == '\"') |
| 68 | dstr_putc(d, '\\'); |
| 69 | dstr_putc(d, *p++); |
| 70 | } |
| 71 | dstr_putc(d, '\"'); |
| 72 | } |
| 73 | } |
| 74 | |
| 75 | /* --- @u_getuser@ --- * |
| 76 | * |
| 77 | * Arguments: @const char *name@ = user name or id requested |
| 78 | * @gid_t *gg@ = where to store corresponding gid |
| 79 | * |
| 80 | * Returns: Corresponding uid. |
| 81 | * |
| 82 | * Use: Resolves a user name into a uid. Dies on failure; suitable |
| 83 | * for use in argument parsing. |
| 84 | */ |
| 85 | |
| 86 | uid_t u_getuser(const char *name, gid_t *gg) |
| 87 | { |
| 88 | struct passwd *pw; |
| 89 | char *p; |
| 90 | unsigned long i = strtoul(name, &p, 0); |
| 91 | |
| 92 | if (!*p) |
| 93 | pw = getpwuid(i); |
| 94 | else |
| 95 | pw = getpwnam(name); |
| 96 | if (!pw) |
| 97 | die(EXIT_FAILURE, "user `%s' not found", name); |
| 98 | if (gg && *gg == -1) |
| 99 | *gg = pw->pw_gid; |
| 100 | return (pw->pw_uid); |
| 101 | } |
| 102 | |
| 103 | /* --- @u_getgroup@ --- * |
| 104 | * |
| 105 | * Arguments: @const char *name@ = user name or id requested |
| 106 | * |
| 107 | * Returns: Corresponding gid. |
| 108 | * |
| 109 | * Use: Resolves a group name into a gid. Dies on failure; suitable |
| 110 | * for use in argument parsing. |
| 111 | */ |
| 112 | |
| 113 | gid_t u_getgroup(const char *name) |
| 114 | { |
| 115 | struct group *gr; |
| 116 | char *p; |
| 117 | unsigned long i = strtoul(name, &p, 0); |
| 118 | |
| 119 | if (!*p) |
| 120 | gr = getgrgid(i); |
| 121 | else |
| 122 | gr = getgrnam(name); |
| 123 | if (!gr) |
| 124 | die(EXIT_FAILURE, "group `%s' not found", name); |
| 125 | return (gr->gr_gid); |
| 126 | } |
| 127 | |
| 128 | /* --- @u_setugid@ --- * |
| 129 | * |
| 130 | * Arguments: @uid_t u@ = user to set |
| 131 | * @gid_t g@ = group to set |
| 132 | * |
| 133 | * Returns: --- |
| 134 | * |
| 135 | * Use: Sets user and group to the given values; aborts on failure. |
| 136 | */ |
| 137 | |
| 138 | void u_setugid(uid_t u, gid_t g) |
| 139 | { |
| 140 | uid_t cu = geteuid(); |
| 141 | |
| 142 | if (cu == 0 && g != (gid_t)-1) { |
| 143 | if (setgid(g) || (getuid() == 0 && setgroups(1, &g))) { |
| 144 | die(EXIT_FAILURE, "couldn't setgid to %u: %s", |
| 145 | (unsigned)g, strerror(errno)); |
| 146 | } |
| 147 | } |
| 148 | if (u != (uid_t)-1) { |
| 149 | if (setuid(u)) { |
| 150 | die(EXIT_FAILURE, "couldn't setuid to %u: %s", |
| 151 | (unsigned)u, strerror(errno)); |
| 152 | } |
| 153 | } |
| 154 | } |
| 155 | |
| 156 | /*----- That's all, folks -------------------------------------------------*/ |