Small tweaks:

[opendoas.git] / doas.c

diff --git a/doas.c b/doas.c
index ac15f50955d1a79ff03a2fa7846cf1c762c6ee13..004076cf62e018d4a48eab07384d188d45a3235e 100644 (file)
--- a/doas.c
+++ b/doas.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: doas.c,v 1.8 2015/07/18 06:33:23 nicm Exp $ */
+/* $OpenBSD: doas.c,v 1.19 2015/07/22 05:37:23 deraadt Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
  *
@@ -29,13 +29,14 @@
 #include <pwd.h>
 #include <grp.h>
 #include <syslog.h>
+#include <errno.h>
 
 #include "doas.h"
 
 static void __dead
 usage(void)
 {
-       fprintf(stderr, "usage: doas [-s] [-u user] command [args]\n");
+       fprintf(stderr, "usage: doas [-s] [-C config] [-u user] command [args]\n");
        exit(1);
 }
 
@@ -96,7 +97,7 @@ strtogid(const char *s)
 
 static int
 match(uid_t uid, gid_t *groups, int ngroups, uid_t target, const char *cmd,
-    struct rule *r)
+    const char **cmdargs, struct rule *r)
 {
        int i;
 
@@ -116,20 +117,33 @@ match(uid_t uid, gid_t *groups, int ngroups, uid_t target, const char *cmd,
        }
        if (r->target && uidcheck(r->target, target) != 0)
                return 0;
-       if (r->cmd && strcmp(r->cmd, cmd) != 0)
-               return 0;
+       if (r->cmd) {
+               if (strcmp(r->cmd, cmd))
+                       return 0;
+               if (r->cmdargs) {
+                       /* if arguments were given, they should match explicitly */
+                       for (i = 0; r->cmdargs[i]; i++) {
+                               if (!cmdargs[i])
+                                       return 0;
+                               if (strcmp(r->cmdargs[i], cmdargs[i]))
+                                       return 0;
+                       }
+                       if (cmdargs[i])
+                               return 0;
+               }
+       }
        return 1;
 }
 
 static int
 permit(uid_t uid, gid_t *groups, int ngroups, struct rule **lastr,
-    uid_t target, const char *cmd)
+    uid_t target, const char *cmd, const char **cmdargs)
 {
        int i;
 
        *lastr = NULL;
        for (i = 0; i < nrules; i++) {
-               if (match(uid, groups, ngroups, target, cmd, rules[i]))
+               if (match(uid, groups, ngroups, target, cmd, cmdargs, rules[i]))
                        *lastr = rules[i];
        }
        if (!*lastr)
@@ -187,34 +201,52 @@ static char **
 copyenv(const char **oldenvp, struct rule *rule)
 {
        const char *safeset[] = {
-               "DISPLAY", "HOME", "LOGNAME", "MAIL", "SHELL",
+               "DISPLAY", "HOME", "LOGNAME", "MAIL",
                "PATH", "TERM", "USER", "USERNAME",
-               NULL,
+               NULL
+       };
+       const char *badset[] = {
+               "ENV",
+               NULL
        };
        char **envp;
        const char **extra;
        int ei;
-       int i, j;
-       int nsafe;
+       int nsafe, nbad;
        int nextras = 0;
-       
+
+       nbad = arraylen(badset);
        if ((rule->options & KEEPENV) && !rule->envlist) {
-               j = arraylen(oldenvp);
-               envp = reallocarray(NULL, j + 1, sizeof(char *));
+               size_t i, ii;
+               size_t oldlen = arraylen(oldenvp);
+               envp = reallocarray(NULL, oldlen + 1, sizeof(char *));
                if (!envp)
                        err(1, "reallocarray");
-               for (i = 0; i < j; i++) {
-                       if (!(envp[i] = strdup(oldenvp[i])))
-                               err(1, "strdup");
+               for (ii = i = 0; i < oldlen; i++) {
+                       size_t j;
+                       for (j = 0; j < nbad; j++) {
+                               size_t len = strlen(badset[j]);
+                               if (strncmp(oldenvp[i], badset[j], len) == 0 &&
+                                   oldenvp[i][len] == '=') {
+                                       break;
+                               }
+                       }
+                       if (j == nbad) {
+                               if (!(envp[ii] = strdup(oldenvp[i])))
+                                       err(1, "strdup");
+                               ii++;
+                       }
                }
-               envp[i] = NULL;
+               envp[ii] = NULL;
                return envp;
        }
 
        nsafe = arraylen(safeset);
        if ((extra = rule->envlist)) {
+               size_t i;
                nextras = arraylen(extra);
                for (i = 0; i < nsafe; i++) {
+                       size_t j;
                        for (j = 0; j < nextras; j++) {
                                if (strcmp(extra[j], safeset[i]) == 0) {
                                        extra[j--] = extra[nextras--];
@@ -262,10 +294,13 @@ main(int argc, char **argv, char **envp)
        int i, ch;
        int sflag = 0;
 
-       parseconfig("/etc/doas.conf");
-
-       while ((ch = getopt(argc, argv, "su:")) != -1) {
+       uid = getuid();
+       while ((ch = getopt(argc, argv, "C:su:")) != -1) {
                switch (ch) {
+               case 'C':
+                       setresuid(uid, uid, uid);
+                       parseconfig(optarg);
+                       exit(0);
                case 'u':
                        if (parseuid(optarg, &target) != 0)
                                errx(1, "unknown user");
@@ -284,7 +319,8 @@ main(int argc, char **argv, char **envp)
        if ((!sflag && !argc) || (sflag && argc))
                usage();
 
-       uid = getuid();
+       parseconfig("/etc/doas.conf");
+
        pw = getpwuid(uid);
        if (!pw)
                err(1, "getpwuid failed");
@@ -315,7 +351,8 @@ main(int argc, char **argv, char **envp)
                        errx(1, "command line too long");
        }
 
-       if (!permit(uid, groups, ngroups, &rule, target, cmd)) {
+       if (!permit(uid, groups, ngroups, &rule, target, cmd,
+           (const char**)argv + 1)) {
                syslog(LOG_AUTHPRIV | LOG_NOTICE,
                    "failed command for %s: %s", myname, cmdline);
                fail();
@@ -343,5 +380,7 @@ main(int argc, char **argv, char **envp)
        if (setenv("PATH", safepath, 1) == -1)
                err(1, "failed to set PATH '%s'", safepath);
        execvpe(cmd, argv, envp);
+       if (errno == ENOENT)
+               errx(1, "%s: command not found", cmd);
        err(1, "%s", cmd);
 }