getpwuid_r and getpwnam_r prototypes.

1 files changed, 80 insertions, 14 deletions

diff --git a/nss-rainbow.c b/nss-rainbow.c
index f898ecc..f0fc376 100644
--- a/nss-rainbow.c
+++ b/nss-rainbow.c
@@ -39,6 +39,22 @@ _nss_rainbow_setpwent(void) {
   g_done = false;
 }
 
+int write_buf(char* home, char** buf, size_t * buflen)
+{
+  size_t homelen;
+  homelen = strnlen(home, *buflen);
+  if (homelen == *buflen)
+  {
+    errno = ERANGE;
+    return -1;
+  }
+  strncpy(*buf, home, homelen);
+  (*buf)[homelen] = '\0';
+  *buflen -= homelen + 1;
+  *buf += homelen + 1;
+  return 0;
+}
+
 enum nss_status
 _nss_rainbow_getpwent_r(struct passwd *result, char* buf, size_t buflen, int *errnop) {
   /* I'm going to interpret the reentrancy requirement on this function to mean
@@ -56,23 +72,15 @@ _nss_rainbow_getpwent_r(struct passwd *result, char* buf, size_t buflen, int *er
       getenv("USER"),
       out_error_unavail, "Unable to retrieve $USER.");
 
-  LET(size_t, homelen, buflen,
-      strnlen(home, buflen),
-      out_error_buffer, "$HOME too long.");
-  strncpy(buf, home, homelen);
   result->pw_dir = buf;
-  buf[homelen] = '\0';
-  buf += homelen + 1;
-  buflen -= homelen + 1;
+  CHECK(int, -1,
+    write_buf(home, &buf, &buflen),
+    out_error_buffer, "Not enough buffer for $HOME.");
 
-  LET(size_t, userlen, buflen,
-      strnlen(user, buflen),
-      out_error_buffer, "$USER too long.");
-  strncpy(buf, user, userlen);
   result->pw_gecos = result->pw_name = result->pw_passwd = buf;
-  buf[userlen] = '\0';
-  buf += userlen + 1;
-  buflen -= userlen + 1;
+  CHECK(int, -1,
+    write_buf(user, &buf, &buflen),
+    out_error_buffer, "Not enough buffer for $USER.");
 
   CHECK(bool, true,
       strlen(SHELL) > buflen,
@@ -95,3 +103,61 @@ out_error_buffer:
   *errnop = ERANGE;
   return NSS_STATUS_TRYAGAIN;
 }
+
+enum nss_status _nss_rainbow_getpwbyuid_r(uid_t uid, struct passwd *result, char* buf, size_t buflen, int *errnop) {
+  if (uid < 10000)
+      return NSS_STATUS_NOTFOUND;
+  int homelen = snprintf(buf, buflen, "/home/olpc/isolation/1/%d", uid);
+  if ((homelen <= 0) || (((unsigned int) homelen) >= buflen)) {
+    PERROR("Insufficient HOMEBUFLEN for the home for user uid.");
+    goto out_error_buffer;}
+  buf[homelen] = '\0';
+  struct stat statbuf;
+  CHECK(int, -1,
+    stat(buf, &statbuf),
+    out_error_errno, "Stat failed for homebuf.");
+  result->pw_uid = uid;
+  result->pw_gid = statbuf.st_gid;
+  result->pw_dir = buf;
+  buf += homelen + 1;
+  buflen -= homelen + 1;
+  homelen = snprintf(buf, buflen, "%d", uid);
+  if ((homelen <= 0) || (((unsigned int ) homelen ) >= buflen)) {
+    PERROR("Insufficient HOMEBUFLEN for user uid as a string.");
+    goto out_error_buffer;
+  }
+  result->pw_gecos = result->pw_name = result->pw_passwd = buf;
+  buf += homelen + 1;
+  buflen -= homelen + 1;
+  CHECK(bool, true,
+      strlen(SHELL) > buflen,
+      out_error_buffer, "Shell string constant too long.");
+  strcpy(buf, SHELL);
+  result->pw_shell = buf;
+  // DO NOT USE BUF UNLESS YOU INCREMENT IT NOW.
+  // YOU ARE DONE.
+
+  return NSS_STATUS_SUCCESS;
+
+out_error_buffer:
+  *errnop = ERANGE;
+  return NSS_STATUS_TRYAGAIN;
+out_error_errno:
+  return NSS_STATUS_TRYAGAIN;
+}
+enum nss_status _nss_rainbow_getpwbynam_r(const char * name, struct passwd *result, char* buf, size_t buflen, int *errnop) {
+  const char * endptr = name + strlen(name);
+  char * endptrt = (char *) (uintptr_t) endptr;
+  long uid = strtol(name, &endptrt, 10);
+  if (endptr != endptrt) {
+    PERROR("Entire name is not an integer.");
+    goto out_error_badname;
+  }
+
+  // YOU ARE DONE.
+  return _nss_rainbow_getpwbyuid_r((uid_t)uid, result, buf, buflen, errnop);
+
+out_error_badname:
+  *errnop = EINVAL;
+  return NSS_STATUS_NOTFOUND;
+}