Merge branch 'release/debian/4.10-1'debian/4.10-1

1 files changed, 150 insertions, 36 deletions

diff --git a/src/proc.c b/src/proc.c
index a7b47aa..1151fff 100644
--- a/src/proc.c
+++ b/src/proc.c
@@ -7,42 +7,118 @@
  *	General Public License as published by the Free Software Foundation;
  *	either version 2.1 or (at your option) any later version.
  */
-#include "config.h"
+#ifdef HAVE_CONFIG_H
+#	include "config.h"
+#endif
 #include "internal.h"
-
-#if !defined(HAVE_FORK) || !defined(HAVE_PIPE) || !defined(HAVE_EXECV) || \
-    !defined(HAVE_EXECVP)
 #include <errno.h>
+#include <limits.h>
+#include <unistd.h>
+#ifdef HAVE_SYS_RESOURCE_H
+#	include <sys/resource.h>
+#endif
 #include <libHX/proc.h>
+#ifdef _WIN32
+#	include <winsock2.h>
+#endif
 
-struct HXproc;
+#if defined(HAVE_INITGROUPS) && defined(HAVE_SETGID)
+#include <grp.h>
+#include <pwd.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <unistd.h>
 
-EXPORT_SYMBOL int HXproc_run_async(const char *const *argv, struct HXproc *p)
+static int HXproc_switch_gid(const struct passwd *pw, gid_t gr_gid)
 {
-	return -ENOSYS;
+	bool do_setgid = getgid() != gr_gid || getegid() != gr_gid;
+	if (do_setgid && setgid(gr_gid) != 0) {
+		if (errno == 0)
+			errno = -EINVAL;
+		return HXPROC_SETGID_FAILED;
+	}
+	if (pw == NULL)
+		return do_setgid ? HXPROC_SU_SUCCESS : HXPROC_SU_NOOP;
+
+	/* pw!=NULL: user switch requested, do initgroups now. */
+
+	if (geteuid() == pw->pw_uid) {
+		/*
+		 * Target identity (usually unprivileged) already reached.
+		 * initgroups is unlikely to succeed.
+		 */
+		if (initgroups(pw->pw_name, gr_gid) < 0)
+			/* ignore */;
+		return do_setgid ? HXPROC_SU_SUCCESS : HXPROC_SU_NOOP;
+	}
+	if (initgroups(pw->pw_name, gr_gid) != 0)
+		return HXPROC_INITGROUPS_FAILED;
+	return do_setgid ? HXPROC_SU_SUCCESS : HXPROC_SU_NOOP;
 }
 
-EXPORT_SYMBOL int HXproc_run_sync(const char *const *argv, unsigned int flags)
+static int HXproc_switch_group(const struct passwd *pw, const char *group)
 {
-	/* Might use system() here... */
-	return -ENOSYS;
+	char *end;
+	unsigned long gid = strtoul(group, &end, 10);
+	const struct group *gr = *end == '\0' ? getgrgid(gid) : getgrnam(group);
+	if (gr == NULL) {
+		if (errno == 0)
+			errno = ENOENT;
+		return HXPROC_GROUP_NOT_FOUND;
+	}
+	return HXproc_switch_gid(pw, gr->gr_gid);
 }
 
-EXPORT_SYMBOL int HXproc_wait(struct HXproc *p)
+EXPORT_SYMBOL int HXproc_switch_user(const char *user, const char *group)
+{
+	const struct passwd *pw = NULL;
+	if (user != NULL && *user != '\0') {
+		char *end;
+		unsigned long uid = strtoul(user, &end, 10);
+		pw = *end == '\0' ? getpwuid(uid) : getpwnam(user);
+		if (pw == NULL) {
+			if (errno == 0)
+				errno = ENOENT;
+			return HXPROC_USER_NOT_FOUND;
+		}
+	}
+	int ret = HXPROC_SU_NOOP;
+	if (group != NULL && *group != '\0') {
+		ret = HXproc_switch_group(pw, group);
+		if (ret < 0)
+			return ret;
+	} else if (group == NULL && pw != NULL) {
+		ret = HXproc_switch_gid(pw, pw->pw_gid);
+		if (ret < 0)
+			return ret;
+	}
+	bool do_setuid = pw != NULL && (getuid() != pw->pw_uid || geteuid() != pw->pw_uid);
+	if (do_setuid && setuid(pw->pw_uid) != 0) {
+		if (errno == 0)
+			errno = -EINVAL;
+		return HXPROC_SETUID_FAILED;
+	}
+	return do_setuid ? HXPROC_SU_SUCCESS : ret;
+}
+
+#else
+
+EXPORT_SYMBOL int HXproc_switch_user(const char *user, const char *group)
 {
 	return -ENOSYS;
 }
 
-#else /* HAVE_FORK, HAVE_PIPE, HAVE_EXECVE */
+#endif /* HAVE_lots */
 
+#if defined(HAVE_FORK) && defined(HAVE_PIPE) && defined(HAVE_EXECV) && \
+    defined(HAVE_EXECVP)
 #include <sys/wait.h>
 #include <fcntl.h>
-#include <errno.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <libHX/defs.h>
-#include <libHX/proc.h>
 #include "internal.h"
 
 #ifdef _WIN32
@@ -88,18 +164,20 @@ HXproc_build_pipes(const struct HXproc *proc, int (*p)[2])
  */
 static void HXproc_close_pipes(int (*p)[2])
 {
+#define xc(fd) do { close(fd); (fd) = -1; } while (false)
 	if (p[0][0] >= 0)
-		close(p[0][0]);
+		xc(p[0][0]);
 	if (p[0][1] >= 0)
-		close(p[0][1]);
+		xc(p[0][1]);
 	if (p[1][0] >= 0)
-		close(p[1][0]);
+		xc(p[1][0]);
 	if (p[1][1] >= 0)
-		close(p[1][1]);
+		xc(p[1][1]);
 	if (p[2][0] >= 0)
-		close(p[2][0]);
+		xc(p[2][0]);
 	if (p[2][1] >= 0)
-		close(p[2][1]);
+		xc(p[2][1]);
+#undef xc
 }
 
 /**
@@ -113,29 +191,27 @@ EXPORT_SYMBOL int
 HXproc_run_async(const char *const *argv, struct HXproc *proc)
 {
 	int pipes[3][2], nullfd = -1, ret, saved_errno;
-	unsigned int t;
 
 	if (argv == NULL || *argv == NULL)
 		return -EFAULT;
-
-	proc->p_stdin = proc->p_stdout = proc->p_stderr = -1;
-
-	t  = (proc->p_flags & (HXPROC_STDIN | HXPROC_NULL_STDIN)) ==
-	     (HXPROC_STDIN | HXPROC_NULL_STDIN);
-	t |= (proc->p_flags & (HXPROC_STDOUT | HXPROC_NULL_STDOUT)) ==
-	     (HXPROC_STDOUT | HXPROC_NULL_STDOUT);
-	t |= (proc->p_flags & (HXPROC_STDERR | HXPROC_NULL_STDERR)) ==
-	     (HXPROC_STDERR | HXPROC_NULL_STDERR);
-	if (t > 0)
+	if ((proc->p_flags & (HXPROC_STDIN | HXPROC_NULL_STDIN)) ==
+	    (HXPROC_STDIN | HXPROC_NULL_STDIN))
+		return -EINVAL;
+	if ((proc->p_flags & (HXPROC_STDOUT | HXPROC_NULL_STDOUT)) ==
+	    (HXPROC_STDOUT | HXPROC_NULL_STDOUT))
+		return -EINVAL;
+	if ((proc->p_flags & (HXPROC_STDERR | HXPROC_NULL_STDERR)) ==
+	    (HXPROC_STDERR | HXPROC_NULL_STDERR))
 		return -EINVAL;
-
 	if (proc->p_flags & (HXPROC_NULL_STDIN | HXPROC_NULL_STDOUT |
 	    HXPROC_NULL_STDERR)) {
 		if ((nullfd = open(NULL_DEVICE, O_RDWR)) < 0)
 			return -errno;
 	}
+	proc->p_stdin = proc->p_stdout = proc->p_stderr = -1;
 	if ((ret = HXproc_build_pipes(proc, pipes)) <= 0) {
 		saved_errno = errno;
+		HXproc_close_pipes(pipes);
 		if (nullfd >= 0)
 			close(nullfd);
 		errno = saved_errno;
@@ -183,17 +259,17 @@ HXproc_run_async(const char *const *argv, struct HXproc *proc)
 		 */
 		HXproc_close_pipes(pipes);
 		if ((proc->p_flags & (HXPROC_STDIN | HXPROC_NULL_STDIN)) &&
-		    proc->p_stdin != STDIN_FILENO) {
+		    proc->p_stdin >= 0 && proc->p_stdin != STDIN_FILENO) {
 			dup2(proc->p_stdin, STDIN_FILENO);
 			close(proc->p_stdin);
 		}
 		if ((proc->p_flags & (HXPROC_STDOUT | HXPROC_NULL_STDOUT)) &&
-		    proc->p_stdout != STDOUT_FILENO) {
+		    proc->p_stdout >= 0 && proc->p_stdout != STDOUT_FILENO) {
 			dup2(proc->p_stdout, STDOUT_FILENO);
 			close(proc->p_stdout);
 		}
 		if ((proc->p_flags & (HXPROC_STDERR | HXPROC_NULL_STDERR)) &&
-		    proc->p_stderr != STDERR_FILENO) {
+		    proc->p_stderr >= 0 && proc->p_stderr != STDERR_FILENO) {
 			dup2(proc->p_stderr, STDERR_FILENO);
 			close(proc->p_stderr);
 		}
@@ -223,7 +299,8 @@ HXproc_run_async(const char *const *argv, struct HXproc *proc)
 		close(pipes[2][1]);
 		proc->p_stderr = pipes[2][0];
 	}
-
+	if (nullfd >= 0)
+		close(nullfd);
 	return 1;
 }
 
@@ -266,4 +343,41 @@ EXPORT_SYMBOL int HXproc_wait(struct HXproc *proc)
 	return static_cast(unsigned char, proc->p_status);
 }
 
+#else
+
+EXPORT_SYMBOL int HXproc_run_async(const char *const *argv, struct HXproc *p)
+{
+	return -ENOSYS;
+}
+
+EXPORT_SYMBOL int HXproc_run_sync(const char *const *argv, unsigned int flags)
+{
+	/* Might use system() here... */
+	return -ENOSYS;
+}
+
+EXPORT_SYMBOL int HXproc_wait(struct HXproc *p)
+{
+	return -ENOSYS;
+}
+
 #endif /* HAVE_lots */
+
+EXPORT_SYMBOL int HXproc_top_fd(void)
+{
+#ifndef _WIN32
+	struct rlimit r;
+	if (getrlimit(RLIMIT_NOFILE, &r) == 0) {
+		if (r.rlim_max > INT_MAX)
+			r.rlim_max = INT_MAX;
+		return r.rlim_max;
+	}
+	long v = sysconf(_SC_OPEN_MAX);
+	if (v >= 0) {
+		if (v > INT_MAX)
+			v = INT_MAX;
+		return v;
+	}
+#endif
+	return FD_SETSIZE;
+}