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--- a/modules/pam_rhosts/pam_rhosts.c
+++ b/modules/pam_rhosts/pam_rhosts.c
@@ -43,6 +43,361 @@
#include <security/pam_modutil.h>
#include <security/pam_ext.h>
+#ifdef __UCLIBC__
+
+#include <stdio.h>
+#include <sys/stat.h>
+
+
+int __check_rhosts_file = 1;
+
+/* Extremely paranoid file open function. */
+static FILE *
+iruserfopen (const char *file, uid_t okuser)
+{
+ struct stat st;
+ char *cp = NULL;
+ FILE *res = NULL;
+
+ /* If not a regular file, if owned by someone other than user or
+ root, if writeable by anyone but the owner, or if hardlinked
+ anywhere, quit. */
+ if (lstat (file, &st))
+ cp = "lstat failed";
+ else if (!S_ISREG (st.st_mode))
+ cp = "not regular file";
+ else
+ {
+ res = fopen (file, "r");
+ if (!res)
+ cp = "cannot open";
+ else if (fstat (fileno (res), &st) < 0)
+ cp = "fstat failed";
+ else if (st.st_uid && st.st_uid != okuser)
+ cp = "bad owner";
+ else if (st.st_mode & (S_IWGRP|S_IWOTH))
+ cp = "writeable by other than owner";
+ else if (st.st_nlink > 1)
+ cp = "hard linked somewhere";
+ }
+
+ /* If there were any problems, quit. */
+ if (cp != NULL)
+ {
+ if (res)
+ fclose (res);
+ return NULL;
+ }
+
+ return res;
+}
+
+/*
+ * Returns 1 for blank lines (or only comment lines) and 0 otherwise
+ */
+static int
+__isempty(char *p)
+{
+ while (*p && isspace (*p)) {
+ ++p;
+ }
+
+ return (*p == '\0' || *p == '#') ? 1 : 0 ;
+}
+
+/* Returns 1 on positive match, 0 on no match, -1 on negative match. */
+static int
+__icheckhost (u_int32_t raddr, char *lhost, const char *rhost)
+{
+ struct hostent *hp;
+ u_int32_t laddr;
+ int negate=1; /* Multiply return with this to get -1 instead of 1 */
+ char **pp;
+
+#ifdef __UCLIBC_HAS_REENTRANT_RPC__
+ int save_errno;
+ size_t buflen;
+ char *buffer;
+ struct hostent hostbuf;
+ int herr;
+#endif
+
+#ifdef HAVE_NETGROUP
+ /* Check nis netgroup. */
+ if (strncmp ("+@", lhost, 2) == 0)
+ return innetgr (&lhost[2], rhost, NULL, NULL);
+
+ if (strncmp ("-@", lhost, 2) == 0)
+ return -innetgr (&lhost[2], rhost, NULL, NULL);
+#endif /* HAVE_NETGROUP */
+
+ /* -host */
+ if (strncmp ("-", lhost,1) == 0) {
+ negate = -1;
+ lhost++;
+ } else if (strcmp ("+",lhost) == 0) {
+ return 1; /* asking for trouble, but ok.. */
+ }
+
+ /* Try for raw ip address first. */
+ if (isdigit (*lhost) && (laddr = inet_addr (lhost)) != INADDR_NONE)
+ return negate * (! (raddr ^ laddr));
+
+ /* Better be a hostname. */
+#ifdef __UCLIBC_HAS_REENTRANT_RPC__
+ buflen = 1024;
+ buffer = malloc(buflen);
+ save_errno = errno;
+
+ while (gethostbyname_r (lhost, &hostbuf, buffer, buflen, &hp, &herr)
+ != 0) {
+ free(buffer);
+ return (0);
+ }
+ free(buffer);
+ __set_errno (save_errno);
+#else
+ hp = gethostbyname(lhost);
+#endif /* __UCLIBC_HAS_REENTRANT_RPC__ */
+
+ if (hp == NULL)
+ return 0;
+
+ /* Spin through ip addresses. */
+ for (pp = hp->h_addr_list; *pp; ++pp)
+ if (!memcmp (&raddr, *pp, sizeof (u_int32_t)))
+ return negate;
+
+ /* No match. */
+ return (0);
+}
+
+/* Returns 1 on positive match, 0 on no match, -1 on negative match. */
+static int
+__icheckuser (const char *luser, const char *ruser)
+{
+
+ /*
+ luser is user entry from .rhosts/hosts.equiv file
+ ruser is user id on remote host
+ */
+
+#ifdef HAVE_NETGROUP
+ /* [-+]@netgroup */
+ if (strncmp ("+@", luser, 2) == 0)
+ return innetgr (&luser[2], NULL, ruser, NULL);
+
+ if (strncmp ("-@", luser,2) == 0)
+ return -innetgr (&luser[2], NULL, ruser, NULL);
+#endif /* HAVE_NETGROUP */
+
+ /* -user */
+ if (strncmp ("-", luser, 1) == 0)
+ return -(strcmp (&luser[1], ruser) == 0);
+
+ /* + */
+ if (strcmp ("+", luser) == 0)
+ return 1;
+
+ /* simple string match */
+ return strcmp (ruser, luser) == 0;
+}
+
+/*
+ * Returns 0 if positive match, -1 if _not_ ok.
+ */
+static int
+__ivaliduser2(FILE *hostf, u_int32_t raddr, const char *luser,
+ const char *ruser, const char *rhost)
+{
+ register const char *user;
+ register char *p;
+ int hcheck, ucheck;
+ char *buf = NULL;
+ size_t bufsize = 0;
+ int retval = -1;
+
+ while (getline (&buf, &bufsize, hostf) > 0) {
+ buf[bufsize - 1] = '\0'; /* Make sure it's terminated. */
+ p = buf;
+
+ /* Skip empty or comment lines */
+ if (__isempty (p)) {
+ continue;
+ }
+
+ /* Skip lines that are too long. */
+ if (strchr (p, '\n') == NULL) {
+ int ch = getc_unlocked (hostf);
+
+ while (ch != '\n' && ch != EOF)
+ ch = getc_unlocked (hostf);
+ continue;
+ }
+
+ for (;*p && !isspace(*p); ++p) {
+ *p = tolower (*p);
+ }
+
+ /* Next we want to find the permitted name for the remote user. */
+ if (*p == ' ' || *p == '\t') {
+ /* <nul> terminate hostname and skip spaces */
+ for (*p++='\0'; *p && isspace (*p); ++p);
+
+ user = p; /* this is the user's name */
+ while (*p && !isspace (*p))
+ ++p; /* find end of user's name */
+ } else
+ user = p;
+
+ *p = '\0'; /* <nul> terminate username (+host?) */
+
+ /* buf -> host(?) ; user -> username(?) */
+
+ /* First check host part */
+ hcheck = __icheckhost (raddr, buf, rhost);
+
+ if (hcheck < 0)
+ break;
+
+ if (hcheck) {
+ /* Then check user part */
+ if (! (*user))
+ user = luser;
+
+ ucheck = __icheckuser (user, ruser);
+
+ /* Positive 'host user' match? */
+ if (ucheck > 0) {
+ retval = 0;
+ break;
+ }
+
+ /* Negative 'host -user' match? */
+ if (ucheck < 0)
+ break;
+
+ /* Neither, go on looking for match */
+ }
+ }
+
+ free (buf);
+
+ return retval;
+}
+
+static int
+iruserok2 (u_int32_t raddr, int superuser, const char *ruser, const char *luser,
+ const char *rhost)
+{
+ FILE *hostf = NULL;
+ int isbad = -1;
+
+ if (!superuser)
+ hostf = iruserfopen (_PATH_HEQUIV, 0);
+
+ if (hostf) {
+ isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
+ fclose (hostf);
+
+ if (!isbad)
+ return 0;
+ }
+
+ if (__check_rhosts_file || superuser) {
+ char *pbuf;
+ struct passwd *pwd;
+ size_t dirlen;
+ uid_t uid;
+
+#ifdef __UCLIBC_HAS_REENTRANT_RPC__
+ size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX);
+ struct passwd pwdbuf;
+ char *buffer = stack_heap_alloc(buflen);
+
+ if (getpwnam_r (luser, &pwdbuf, buffer,
+ buflen, &pwd) != 0 || pwd == NULL)
+ {
+ stack_heap_free(buffer);
+ return -1;
+ }
+ stack_heap_free(buffer);
+#else
+ if ((pwd = getpwnam(luser)) == NULL)
+ return -1;
+#endif
+
+ dirlen = strlen (pwd->pw_dir);
+ pbuf = malloc (dirlen + sizeof "/.rhosts");
+ strcpy (pbuf, pwd->pw_dir);
+ strcat (pbuf, "/.rhosts");
+
+ /* Change effective uid while reading .rhosts. If root and
+ reading an NFS mounted file system, can't read files that
+ are protected read/write owner only. */
+ uid = geteuid ();
+ seteuid (pwd->pw_uid);
+ hostf = iruserfopen (pbuf, pwd->pw_uid);
+ free(pbuf);
+
+ if (hostf != NULL) {
+ isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
+ fclose (hostf);
+ }
+
+ seteuid (uid);
+ return isbad;
+ }
+ return -1;
+}
+
+int ruserok(const char *rhost, int superuser, const char *ruser,
+ const char *luser)
+{
+ struct hostent *hp;
+ u_int32_t addr;
+ char **ap;
+#ifdef __UCLIBC_HAS_REENTRANT_RPC__
+ size_t buflen;
+ char *buffer;
+ int herr;
+ struct hostent hostbuf;
+#endif
+
+#ifdef __UCLIBC_HAS_REENTRANT_RPC__
+ buflen = 1024;
+ buffer = stack_heap_alloc(buflen);
+
+ while (gethostbyname_r (rhost, &hostbuf, buffer,
+ buflen, &hp, &herr) != 0 || hp == NULL)
+ {
+ if (herr != NETDB_INTERNAL || errno != ERANGE) {
+ stack_heap_free(buffer);
+ return -1;
+ } else
+ {
+ /* Enlarge the buffer. */
+ buflen *= 2;
+ stack_heap_free(buffer);
+ buffer = stack_heap_alloc(buflen);
+ }
+ }
+ stack_heap_free(buffer);
+#else
+ if ((hp = gethostbyname(rhost)) == NULL) {
+ return -1;
+ }
+#endif
+ for (ap = hp->h_addr_list; *ap; ++ap) {
+ memmove(&addr, *ap, sizeof(addr));
+ if (iruserok2(addr, superuser, ruser, luser, rhost) == 0)
+ return 0;
+ }
+ return -1;
+}
+
+#endif /* __UCLIBC__ */
+
PAM_EXTERN
int pam_sm_authenticate (pam_handle_t *pamh, int flags, int argc,
const char **argv)