]> git.armaanb.net Git - opendoas.git/blobdiff - doas.c
revise environment handling. Add a setenv keyword for manipulating the environment...
[opendoas.git] / doas.c
diff --git a/doas.c b/doas.c
index f1b2ec058be2bb7d992679c523ca0b08334e094a..c1b822b56d9d7f32faa18496bf91d131bcbb314b 100644 (file)
--- a/doas.c
+++ b/doas.c
@@ -28,6 +28,9 @@
 #include <grp.h>
 #include <syslog.h>
 #include <errno.h>
+#if HAVE_SHADOW_H
+#include <shadow.h>
+#endif
 
 #include "includes.h"
 
@@ -190,105 +193,6 @@ parseconfig(const char *filename, int checkperms)
                exit(1);
 }
 
-/*
- * Copy the environment variables in safeset from oldenvp to envp.
- */
-static int
-copyenvhelper(const char **oldenvp, const char **safeset, size_t nsafe,
-    char **envp, int ei)
-{
-       size_t i;
-
-       for (i = 0; i < nsafe; i++) {
-               const char **oe = oldenvp;
-               while (*oe) {
-                       size_t len = strlen(safeset[i]);
-                       if (strncmp(*oe, safeset[i], len) == 0 &&
-                           (*oe)[len] == '=') {
-                               if (!(envp[ei++] = strdup(*oe)))
-                                       err(1, "strdup");
-                               break;
-                       }
-                       oe++;
-               }
-       }
-       return ei;
-}
-
-static char **
-copyenv(const char **oldenvp, struct rule *rule)
-{
-       const char *safeset[] = {
-               "DISPLAY", "HOME", "LOGNAME", "MAIL",
-               "PATH", "TERM", "USER", "USERNAME",
-               NULL
-       };
-       const char *badset[] = {
-               "ENV",
-               NULL
-       };
-       char **envp;
-       const char **extra;
-       int ei;
-       size_t nsafe, nbad;
-       size_t nextras = 0;
-
-       /* if there was no envvar whitelist, pass all except badset ones */
-       nbad = arraylen(badset);
-       if ((rule->options & KEEPENV) && !rule->envlist) {
-               size_t iold, inew;
-               size_t oldlen = arraylen(oldenvp);
-               envp = reallocarray(NULL, oldlen + 1, sizeof(char *));
-               if (!envp)
-                       err(1, "reallocarray");
-               for (inew = iold = 0; iold < oldlen; iold++) {
-                       size_t ibad;
-                       for (ibad = 0; ibad < nbad; ibad++) {
-                               size_t len = strlen(badset[ibad]);
-                               if (strncmp(oldenvp[iold], badset[ibad], len) == 0 &&
-                                   oldenvp[iold][len] == '=') {
-                                       break;
-                               }
-                       }
-                       if (ibad == nbad) {
-                               if (!(envp[inew] = strdup(oldenvp[iold])))
-                                       err(1, "strdup");
-                               inew++;
-                       }
-               }
-               envp[inew] = NULL;
-               return envp;
-       }
-
-       nsafe = arraylen(safeset);
-       if ((extra = rule->envlist)) {
-               size_t isafe;
-               nextras = arraylen(extra);
-               for (isafe = 0; isafe < nsafe; isafe++) {
-                       size_t iextras;
-                       for (iextras = 0; iextras < nextras; iextras++) {
-                               if (strcmp(extra[iextras], safeset[isafe]) == 0) {
-                                       nextras--;
-                                       extra[iextras] = extra[nextras];
-                                       extra[nextras] = NULL;
-                                       iextras--;
-                               }
-                       }
-               }
-       }
-
-       envp = reallocarray(NULL, nsafe + nextras + 1, sizeof(char *));
-       if (!envp)
-               err(1, "can't allocate new environment");
-
-       ei = 0;
-       ei = copyenvhelper(oldenvp, safeset, nsafe, envp, ei);
-       ei = copyenvhelper(oldenvp, rule->envlist, nextras, envp, ei);
-       envp[ei] = NULL;
-
-       return envp;
-}
-
 static void __dead
 checkconfig(const char *confpath, int argc, char **argv,
     uid_t uid, gid_t *groups, int ngroups, uid_t target)
@@ -313,7 +217,7 @@ checkconfig(const char *confpath, int argc, char **argv,
 }
 
 int
-main(int argc, char **argv, char **envp)
+main(int argc, char **argv)
 {
        const char *safepath = "/bin:/sbin:/usr/bin:/usr/sbin:"
            "/usr/local/bin:/usr/local/sbin";
@@ -335,6 +239,7 @@ main(int argc, char **argv, char **envp)
        int vflag = 0;
        char cwdpath[PATH_MAX];
        const char *cwd;
+       char **envp;
 #ifdef HAVE_BSD_AUTH_H
        char *login_style = NULL;
 #endif
@@ -423,7 +328,7 @@ main(int argc, char **argv, char **envp)
        parseconfig("/etc/doas.conf", 1);
 
        /* cmdline is used only for logging, no need to abort on truncate */
-       (void) strlcpy(cmdline, argv[0], sizeof(cmdline));
+       (void)strlcpy(cmdline, argv[0], sizeof(cmdline));
        for (i = 1; i < argc; i++) {
                if (strlcat(cmdline, " ", sizeof(cmdline)) >= sizeof(cmdline))
                        break;
@@ -433,16 +338,12 @@ main(int argc, char **argv, char **envp)
 
        cmd = argv[0];
        if (!permit(uid, groups, ngroups, &rule, target, cmd,
-           (const char**)argv + 1)) {
+           (const char **)argv + 1)) {
                syslog(LOG_AUTHPRIV | LOG_NOTICE,
                    "failed command for %s: %s", myname, cmdline);
                errc(1, EPERM, NULL);
        }
 
-       pw = getpwuid(target);
-       if (!pw)
-               errx(1, "no passwd entry for target");
-
 #ifdef HAVE_BSD_AUTH_H
        if (!(rule->options & NOPASS)) {
                if (nflag)
@@ -477,18 +378,60 @@ main(int argc, char **argv, char **envp)
                explicit_bzero(rbuf, sizeof(rbuf));
        }
 #elif HAVE_PAM_APPL_H
-       if (!doas_pam(pw->pw_name, myname, !nflag, rule->options & NOPASS)) {
+       pw = getpwuid(target);
+       if (!pw)
+               errx(1, "no passwd entry for target");
+
+       if (!pamauth(pw->pw_name, myname, !nflag, rule->options & NOPASS)) {
                syslog(LOG_AUTHPRIV | LOG_NOTICE, "failed auth for %s", myname);
                errc(1, EPERM, NULL);
        }
-#else
+#elif HAVE_SHADOW_H
+       const char *pass;
+
        if (!(rule->options & NOPASS)) {
+               if (nflag)
                        errx(1, "Authorization required");
+
+               pass = pw->pw_passwd;
+               if (pass[0] == 'x' && pass[1] == '\0') {
+                       struct spwd *sp;
+                       if (!(sp = getspnam(myname)))
+                               errx(1, "Authorization failed");
+                       pass = sp->sp_pwdp;
+               }
+
+               char *challenge, *response, rbuf[1024], cbuf[128], host[HOST_NAME_MAX + 1];
+               if (gethostname(host, sizeof(host)))
+                       snprintf(host, sizeof(host), "?");
+               snprintf(cbuf, sizeof(cbuf),
+                               "\rdoas (%.32s@%.32s) password: ", myname, host);
+               challenge = cbuf;
+
+               response = readpassphrase(challenge, rbuf, sizeof(rbuf), RPP_REQUIRE_TTY);
+               if (response == NULL && errno == ENOTTY) {
+                       syslog(LOG_AUTHPRIV | LOG_NOTICE,
+                           "tty required for %s", myname);
+                       errx(1, "a tty is required");
+               }
+               if (strcmp(crypt(response, pass), pass) != 0) {
+                       syslog(LOG_AUTHPRIV | LOG_NOTICE, "failed auth for %s", myname);
+                       errc(1, EPERM, NULL);
+               }
+               explicit_bzero(rbuf, sizeof(rbuf));
+       }
+#else
+       if (!(rule->options & NOPASS))
+               errx(1, "Authorization required");
 #endif /* HAVE_BSD_AUTH_H */
 
        if (pledge("stdio rpath getpw exec id", NULL) == -1)
                err(1, "pledge");
 
+       pw = getpwuid(target);
+       if (!pw)
+               errx(1, "no passwd entry for target");
+
 #ifdef HAVE_BSD_AUTH_H
        if (setusercontext(NULL, pw, target, LOGIN_SETGROUP |
            LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | LOGIN_SETUMASK |
@@ -496,11 +439,11 @@ main(int argc, char **argv, char **envp)
                errx(1, "failed to set user context for target");
 #else
        if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) != 0)
-               errx(1, "setgid");
+               errx(1, "setresgid");
        if (initgroups(pw->pw_name, pw->pw_gid) != 0)
                errx(1, "initgroups");
        if (setresuid(target, target, target) != 0)
-               errx(1, "setuid");
+               errx(1, "setresuid");
 #endif
 
        if (pledge("stdio rpath exec", NULL) == -1)
@@ -517,7 +460,7 @@ main(int argc, char **argv, char **envp)
        syslog(LOG_AUTHPRIV | LOG_INFO, "%s ran command %s as %s from %s",
            myname, cmdline, pw->pw_name, cwd);
 
-       envp = copyenv((const char **)envp, rule);
+       envp = prepenv(rule);
 
        if (rule->cmd) {
                if (setenv("PATH", safepath, 1) == -1)