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Diffstat (limited to 'src/groups.c')
| -rw-r--r-- | src/groups.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/groups.c b/src/groups.c new file mode 100644 index 0000000..fcd669b --- /dev/null +++ b/src/groups.c @@ -0,0 +1,218 @@ +/* + * Copyright (c) 1991 - 1993, Julianne Frances Haugh + * Copyright (c) 1996 - 2000, Marek Michałkiewicz + * Copyright (c) 2001 - 2006, Tomasz Kłoczko + * Copyright (c) 2007 - 2008, Nicolas François + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the copyright holders or contributors may not be used to + * endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <config.h> + +#ident "$Id$" + +#include <grp.h> +#include <pwd.h> +#include <stdio.h> +#include "defines.h" +#include "prototypes.h" +/* + * Global variables + */ +const char *Prog; + +/* local function prototypes */ +static void print_groups (const char *member); + +/* + * print_groups - print the groups which the named user is a member of + * + * print_groups() scans the groups file for the list of groups which + * the user is listed as being a member of. + */ +static void print_groups (const char *member) +{ + int groups = 0; + struct group *grp; + struct passwd *pwd; + bool flag = false; + + pwd = getpwnam (member); /* local, no need for xgetpwnam */ + if (NULL == pwd) { + (void) fprintf (stderr, _("%s: unknown user %s\n"), + Prog, member); + exit (EXIT_FAILURE); + } + + setgrent (); + while ((grp = getgrent ()) != NULL) { + if (is_on_list (grp->gr_mem, member)) { + if (0 != groups) { + (void) putchar (' '); + } + groups++; + + (void) printf ("%s", grp->gr_name); + if (grp->gr_gid == pwd->pw_gid) { + flag = true; + } + } + } + endgrent (); + + /* The user may not be in the list of members of its primary group */ + if (!flag) { + grp = getgrgid (pwd->pw_gid); /* local, no need for xgetgrgid */ + if (NULL != grp) { + if (0 != groups) { + (void) putchar (' '); + } + groups++; + + (void) printf ("%s", grp->gr_name); + } + } + + if (0 != groups) { + (void) putchar ('\n'); + } +} + +/* + * groups - print out the groups a process is a member of + */ +int main (int argc, char **argv) +{ +#ifdef HAVE_GETGROUPS + long sys_ngroups; + GETGROUPS_T *groups; +#else + char *logname; + char *getlogin (); +#endif + +#ifdef HAVE_GETGROUPS + sys_ngroups = sysconf (_SC_NGROUPS_MAX); + groups = (GETGROUPS_T *) malloc (sizeof (GETGROUPS_T) * sys_ngroups); +#endif + (void) setlocale (LC_ALL, ""); + (void) bindtextdomain (PACKAGE, LOCALEDIR); + (void) textdomain (PACKAGE); + + /* + * Get the program name so that error messages can use it. + */ + Prog = Basename (argv[0]); + + if (argc == 1) { + + /* + * Called with no arguments - give the group set for the + * current user. + */ + +#ifdef HAVE_GETGROUPS + int i; + int pri_grp; /* TODO: should be GETGROUPS_T */ + /* + * This system supports concurrent group sets, so I can ask + * the system to tell me which groups are currently set for + * this process. + */ + int ngroups = getgroups (sys_ngroups, groups); + if (ngroups < 0) { + perror ("getgroups"); + exit (EXIT_FAILURE); + } + + /* + * The groupset includes the primary group as well. + */ + pri_grp = getegid (); + for (i = 0; i < ngroups; i++) { + if (pri_grp == (int) groups[i]) { + break; + } + } + + if (i != ngroups) { + pri_grp = -1; + } + + /* + * Print out the name of every group in the current group + * set. Unknown groups are printed as their decimal group ID + * values. + */ + if (-1 != pri_grp) { + struct group *gr; + /* local, no need for xgetgrgid */ + gr = getgrgid (pri_grp); + if (NULL != gr) { + (void) printf ("%s", gr->gr_name); + } else { + (void) printf ("%d", pri_grp); + } + } + + for (i = 0; i < ngroups; i++) { + struct group *gr; + if ((0 != i) || (-1 != pri_grp)) { + (void) putchar (' '); + } + + /* local, no need for xgetgrgid */ + gr = getgrgid (groups[i]); + if (NULL != gr) { + (void) printf ("%s", gr->gr_name); + } else { + (void) printf ("%ld", (long) groups[i]); + } + } + (void) putchar ('\n'); +#else + /* + * This system does not have the getgroups() system call, so + * I must check the groups file directly. + */ + logname = getlogin (); + if (NULL != logname) { + print_groups (logname); + } else { + exit (EXIT_FAILURE); + } +#endif + } else { + + /* + * The invoker wanted to know about some other user. Use + * that name to look up the groups instead. + */ + print_groups (argv[1]); + } + return EXIT_SUCCESS; +} + |