Perform matching in fuzz_sudoers for inputs that parse correctly.

The fuzzer now exercised the normal match code as well as the
pseudo-command (list, validate, etc) match code.
Privileges are also listed for well-formed sudoers file.

plugins/sudoers/Makefile.in

@@ -246,7 +246,8 @@ FUZZ_POLICY_OBJS = fuzz_policy.o editor.lo env.lo env_pattern.lo gc.lo \
 
 FUZZ_POLICY_CORPUS = $(srcdir)/regress/corpus/policy/policy.*
 
-FUZZ_SUDOERS_OBJS = fuzz_sudoers.o locale.lo stubs.o sudo_printf.o
+FUZZ_SUDOERS_OBJS = file.lo fuzz_sudoers.o fmtsudoers.lo parse.lo locale.lo \
+		    stubs.o sudo_printf.o
 
 FUZZ_SUDOERS_CORPUS = $(top_srcdir)/examples/sudoers \
 		      $(srcdir)/regress/sudoers/*.in

plugins/sudoers/regress/fuzz/fuzz_sudoers.c

@@ -16,8 +16,10 @@
 
 #include <config.h>
 
+#include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <fcntl.h>
 #include <unistd.h>
 #if defined(HAVE_STDINT_H)
@@ -28,9 +30,13 @@
 
 #include "sudoers.h"
 
+static int fuzz_conversation(int num_msgs, const struct sudo_conv_message msgs[], struct sudo_conv_reply replies[], struct sudo_conv_callback *callback);
+
 /* Required to link with parser. */
 struct sudo_user sudo_user;
 struct passwd *list_pw;
+sudo_conv_t sudo_conv = fuzz_conversation;
+bool sudoers_recovery = true;
 
 FILE *
 open_sudoers(const char *file, bool doedit, bool *keepopen)
@@ -43,6 +49,74 @@ open_sudoers(const char *file, bool doedit, bool *keepopen)
     return NULL;
 }
 
+static int
+fuzz_conversation(int num_msgs, const struct sudo_conv_message msgs[],
+    struct sudo_conv_reply replies[], struct sudo_conv_callback *callback)
+{
+    int n;
+
+    for (n = 0; n < num_msgs; n++) {
+	const struct sudo_conv_message *msg = &msgs[n];
+	FILE *fp = stdout;
+
+	switch (msg->msg_type & 0xff) {
+	    case SUDO_CONV_PROMPT_ECHO_ON:
+	    case SUDO_CONV_PROMPT_MASK:
+	    case SUDO_CONV_PROMPT_ECHO_OFF:
+		/* input not supported */
+		return -1;
+	    case SUDO_CONV_ERROR_MSG:
+		fp = stderr;
+		FALLTHROUGH;
+	    case SUDO_CONV_INFO_MSG:
+		if (msg->msg != NULL) {
+		    size_t len = strlen(msg->msg);
+
+		    if (len == 0)
+			break;
+
+		    if (fwrite(msg->msg, 1, len, fp) == 0 || fputc('\n', fp) == EOF)
+			return -1;
+		}
+		break;
+	    default:
+		return -1;
+	}
+    }
+    return 0;
+}
+
+bool
+set_perms(int perm)
+{
+    return true;
+}
+
+bool
+restore_perms(void)
+{
+    return true;
+}
+
+bool
+sudo_nss_can_continue(struct sudo_nss *nss, int match)
+{
+    return true;
+}
+
+bool
+log_warningx(int flags, const char *fmt, ...)
+{
+    va_list ap;
+
+    /* Just display on stderr. */
+    va_start(ap, fmt);
+    sudo_vwarnx_nodebug(fmt, ap);
+    va_end(ap);
+
+    return true;
+}
+
 static FILE *
 open_data(const uint8_t *data, size_t size)
 {
@@ -69,9 +143,13 @@ open_data(const uint8_t *data, size_t size)
 #endif
 }
 
+extern struct sudo_nss sudo_nss_file;
+
 int
 LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
 {
+    struct sudo_nss_list snl = TAILQ_HEAD_INITIALIZER(snl);
+    struct sudoers_parse_tree parse_tree;
     FILE *fp;
 
     /* Don't waste time fuzzing tiny inputs. */
@@ -82,16 +160,41 @@ LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     if (fp == NULL)
         return 0;
 
-    /* Parser needs user_shost for the %h escape in @include expansion. */
-    user_host = user_shost = "localhost";
+    /* The minimum needed to perform matching. */
+    user_host = user_shost = user_runhost = user_srunhost = "localhost";
+    user_name = "nobody";
+    user_cmnd = "/usr/bin/id";
+    user_args = "-u";
+    user_base = "id";
+    sudo_user.pw = sudo_getpwnam("root");
+    runas_pw = sudo_getpwnam("root");
+
+    /* Only one sudoers source, the sudoers file itself. */
+    TAILQ_INSERT_TAIL(&snl, &sudo_nss_file, entries);
+    init_parse_tree(&parse_tree, user_host, user_shost);
+    sudo_nss_file.parse_tree = &parse_tree;
 
     /* Initialize defaults and parse sudoers. */
     init_defaults();
     init_parser("sudoers", false, true);
     sudoersrestart(fp);
     sudoersparse();
+    reparent_parse_tree(&parse_tree);
+
+    if (!parse_error) {
+	/* Match command against parsed policy. */
+	int cmnd_status;
+	sudoers_lookup(&snl, sudo_user.pw, &cmnd_status, false);
+
+	/* Match again as a pseudo-command (list, validate, etc). */
+	sudoers_lookup(&snl, sudo_user.pw, &cmnd_status, true);
+
+	/* Display privileges. */
+	display_privs(&snl, sudo_user.pw, false);
+    }
 
     /* Cleanup. */
+    free_parse_tree(&parse_tree);
     init_parser(NULL, false, true);
     fclose(fp);