dhcp: Properly handle unsuccessful cases for DHCP Ack

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index 66276aa54e3925aa6c21225bd39f71a6616de4ec..cdc58e394f1e77fbe9ed329dc2054ae299d03c77 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -4936,15 +4936,15 @@ int fd_inc_sndbuf(int fd, size_t n) {
         socklen_t l = sizeof(value);
 
         r = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, &l);
-        if (r >= 0 &&
-            l == sizeof(value) &&
-            (size_t) value >= n*2)
+        if (r >= 0 && l == sizeof(value) && (size_t) value >= n*2)
                 return 0;
 
+        /* If we have the privileges we will ignore the kernel limit. */
+
         value = (int) n;
-        r = setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, sizeof(value));
-        if (r < 0)
-                return -errno;
+        if (setsockopt(fd, SOL_SOCKET, SO_SNDBUFFORCE, &value, sizeof(value)) < 0)
+                if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &value, sizeof(value)) < 0)
+                        return -errno;
 
         return 1;
 }
@@ -4954,16 +4954,15 @@ int fd_inc_rcvbuf(int fd, size_t n) {
         socklen_t l = sizeof(value);
 
         r = getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &value, &l);
-        if (r >= 0 &&
-            l == sizeof(value) &&
-            (size_t) value >= n*2)
+        if (r >= 0 && l == sizeof(value) && (size_t) value >= n*2)
                 return 0;
 
-        value = (int) n;
-        r = setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &value, sizeof(value));
-        if (r < 0)
-                return -errno;
+        /* If we have the privileges we will ignore the kernel limit. */
 
+        value = (int) n;
+        if (setsockopt(fd, SOL_SOCKET, SO_RCVBUFFORCE, &value, sizeof(value)) < 0)
+                if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &value, sizeof(value)) < 0)
+                        return -errno;
         return 1;
 }
 
@@ -5220,10 +5219,10 @@ int make_console_stdio(void) {
 }
 
 int get_home_dir(char **_h) {
-        char *h;
+        struct passwd *p;
         const char *e;
+        char *h;
         uid_t u;
-        struct passwd *p;
 
         assert(_h);
 
@@ -5266,6 +5265,53 @@ int get_home_dir(char **_h) {
         return 0;
 }
 
+int get_shell(char **_s) {
+        struct passwd *p;
+        const char *e;
+        char *s;
+        uid_t u;
+
+        assert(_s);
+
+        /* Take the user specified one */
+        e = getenv("SHELL");
+        if (e) {
+                s = strdup(e);
+                if (!s)
+                        return -ENOMEM;
+
+                *_s = s;
+                return 0;
+        }
+
+        /* Hardcode home directory for root to avoid NSS */
+        u = getuid();
+        if (u == 0) {
+                s = strdup("/bin/sh");
+                if (!s)
+                        return -ENOMEM;
+
+                *_s = s;
+                return 0;
+        }
+
+        /* Check the database... */
+        errno = 0;
+        p = getpwuid(u);
+        if (!p)
+                return errno > 0 ? -errno : -ESRCH;
+
+        if (!path_is_absolute(p->pw_shell))
+                return -EINVAL;
+
+        s = strdup(p->pw_shell);
+        if (!s)
+                return -ENOMEM;
+
+        *_s = s;
+        return 0;
+}
+
 bool filename_is_safe(const char *p) {
 
         if (isempty(p))
@@ -5983,18 +6029,24 @@ int container_get_leader(const char *machine, pid_t *pid) {
         return 0;
 }
 
-int namespace_open(pid_t pid, int *namespace_fd, int *root_fd) {
-        _cleanup_close_ int nsfd = -1;
-        const char *ns, *root;
+int namespace_open(pid_t pid, int *pidns_fd, int *mntns_fd, int *root_fd) {
+        _cleanup_close_ int pidnsfd = -1, mntnsfd = -1;
+        const char *pidns, *mntns, *root;
         int rfd;
 
         assert(pid >= 0);
-        assert(namespace_fd);
+        assert(pidns_fd);
+        assert(mntns_fd);
         assert(root_fd);
 
-        ns = procfs_file_alloca(pid, "ns/mnt");
-        nsfd = open(ns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
-        if (nsfd < 0)
+        mntns = procfs_file_alloca(pid, "ns/mnt");
+        mntnsfd = open(mntns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+        if (mntnsfd < 0)
+                return -errno;
+
+        pidns = procfs_file_alloca(pid, "ns/pid");
+        pidnsfd = open(pidns, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+        if (pidnsfd < 0)
                 return -errno;
 
         root = procfs_file_alloca(pid, "root");
@@ -6002,18 +6054,24 @@ int namespace_open(pid_t pid, int *namespace_fd, int *root_fd) {
         if (rfd < 0)
                 return -errno;
 
-        *namespace_fd = nsfd;
+        *pidns_fd = pidnsfd;
+        *mntns_fd = mntnsfd;
         *root_fd = rfd;
-        nsfd = -1;
+        pidnsfd = -1;
+        mntnsfd = -1;
 
         return 0;
 }
 
-int namespace_enter(int namespace_fd, int root_fd) {
-        assert(namespace_fd >= 0);
+int namespace_enter(int pidns_fd, int mntns_fd, int root_fd) {
+        assert(pidns_fd >= 0);
+        assert(mntns_fd >= 0);
         assert(root_fd >= 0);
 
-        if (setns(namespace_fd, CLONE_NEWNS) < 0)
+        if (setns(pidns_fd, CLONE_NEWPID) < 0)
+                return -errno;
+
+        if (setns(mntns_fd, CLONE_NEWNS) < 0)
                 return -errno;
 
         if (fchdir(root_fd) < 0)
@@ -6022,5 +6080,11 @@ int namespace_enter(int namespace_fd, int root_fd) {
         if (chroot(".") < 0)
                 return -errno;
 
+        if (setresgid(0, 0, 0) < 0)
+                return -errno;
+
+        if (setresuid(0, 0, 0) < 0)
+                return -errno;
+
         return 0;
 }