privsep: Check if we have a root process before sending it stuff

Fixes #210

diff --git a/src/privsep-bpf.c b/src/privsep-bpf.c
index 2e92026f50cd53a2582b416820a5e1c8c7a5a03a..989400902d7879e9367109daa46429223366d4a3 100644 (file)
--- a/src/privsep-bpf.c
+++ b/src/privsep-bpf.c
@@ -328,7 +328,7 @@ ps_bpf_send(const struct interface *ifp, const struct in_addr *ia,
        if (ia != NULL)
                psm.ps_id.psi_addr.psa_in_addr = *ia;
 
-       return ps_sendpsmdata(ctx, ctx->ps_root->psp_fd, &psm, data, len);
+       return ps_sendpsmdata(ctx, PS_ROOT_FD(ctx), &psm, data, len);
 }
 
 #ifdef ARP

diff --git a/src/privsep-bsd.c b/src/privsep-bsd.c
index b005f93f7e493ccff9a3d768e48b12991026fa56..755ad6d530d62fbd33688b03aeb10d44bbc5b4f2 100644 (file)
--- a/src/privsep-bsd.c
+++ b/src/privsep-bsd.c
@@ -301,7 +301,7 @@ ps_root_ioctldom(struct dhcpcd_ctx *ctx, uint16_t domain, unsigned long request,
     void *data, size_t len)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, domain,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), domain,
            request, data, len) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
@@ -327,7 +327,7 @@ ssize_t
 ps_root_route(struct dhcpcd_ctx *ctx, void *data, size_t len)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_ROUTE, 0, data, len) == -1)
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_ROUTE, 0, data, len) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
 }
@@ -346,7 +346,7 @@ ps_root_indirectioctl(struct dhcpcd_ctx *ctx, unsigned long request,
 
        strlcpy(buf, ifname, IFNAMSIZ);
        memcpy(buf + IFNAMSIZ, data, len);
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_IOCTLINDIRECT,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_IOCTLINDIRECT,
            request, buf, IFNAMSIZ + len) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
@@ -358,7 +358,7 @@ ssize_t
 ps_root_ifignoregroup(struct dhcpcd_ctx *ctx, const char *ifname)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_IFIGNOREGRP, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_IFIGNOREGRP, 0,
            ifname, strlen(ifname) + 1) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -400,7 +400,7 @@ ps_root_sysctl(struct dhcpcd_ctx *ctx,
                p += newlen;
        }
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_SYSCTL,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_SYSCTL,
            flags, buf, (size_t)(p - buf)) == -1)
                return -1;
 

diff --git a/src/privsep-inet.c b/src/privsep-inet.c
index e59c33538148212963e88ad481d672fbbc848e8b..5895a5730c1f097c4c8ee0b2235cc854b02f20f4 100644 (file)
--- a/src/privsep-inet.c
+++ b/src/privsep-inet.c
@@ -622,7 +622,7 @@ ps_inet_in_docmd(struct ipv4_addr *ia, uint16_t cmd, const struct msghdr *msg)
                },
        };
 
-       return ps_sendpsmmsg(ctx, ctx->ps_root->psp_fd, &psm, msg);
+       return ps_sendpsmmsg(ctx, PS_ROOT_FD(ctx), &psm, msg);
 }
 
 ssize_t
@@ -644,7 +644,7 @@ ps_inet_sendbootp(struct interface *ifp, const struct msghdr *msg)
 {
        struct dhcpcd_ctx *ctx = ifp->ctx;
 
-       return ps_sendmsg(ctx, ctx->ps_root->psp_fd, PS_BOOTP, 0, msg);
+       return ps_sendmsg(ctx, PS_ROOT_FD(ctx), PS_BOOTP, 0, msg);
 }
 #endif /* INET */
 
@@ -663,7 +663,7 @@ ps_inet_ifp_docmd(struct interface *ifp, uint16_t cmd, const struct msghdr *msg)
                },
        };
 
-       return ps_sendpsmmsg(ctx, ctx->ps_root->psp_fd, &psm, msg);
+       return ps_sendpsmmsg(ctx, PS_ROOT_FD(ctx), &psm, msg);
 }
 
 ssize_t
@@ -692,7 +692,7 @@ ps_inet_sendnd(struct interface *ifp, const struct msghdr *msg)
 {
        struct dhcpcd_ctx *ctx = ifp->ctx;
 
-       return ps_sendmsg(ctx, ctx->ps_root->psp_fd, PS_ND, 0, msg);
+       return ps_sendmsg(ctx, PS_ROOT_FD(ctx), PS_ND, 0, msg);
 }
 #endif
 
@@ -711,7 +711,7 @@ ps_inet_in6_docmd(struct ipv6_addr *ia, uint16_t cmd, const struct msghdr *msg)
                },
        };
 
-       return ps_sendpsmmsg(ctx, ctx->ps_root->psp_fd, &psm, msg);
+       return ps_sendpsmmsg(ctx, PS_ROOT_FD(ctx), &psm, msg);
 }
 
 ssize_t
@@ -733,7 +733,7 @@ ps_inet_senddhcp6(struct interface *ifp, const struct msghdr *msg)
 {
        struct dhcpcd_ctx *ctx = ifp->ctx;
 
-       return ps_sendmsg(ctx, ctx->ps_root->psp_fd, PS_DHCP6, 0, msg);
+       return ps_sendmsg(ctx, PS_ROOT_FD(ctx), PS_DHCP6, 0, msg);
 }
 #endif /* DHCP6 */
 #endif /* INET6 */

diff --git a/src/privsep-linux.c b/src/privsep-linux.c
index 28d009741098adf4943ce19032b0e0f84841ac61..8270056e1723280ba63386318a6a5f59736b4058 100644 (file)
--- a/src/privsep-linux.c
+++ b/src/privsep-linux.c
@@ -107,7 +107,7 @@ ssize_t
 ps_root_sendnetlink(struct dhcpcd_ctx *ctx, int protocol, struct msghdr *msg)
 {
 
-       if (ps_sendmsg(ctx, ctx->ps_root->psp_fd, PS_ROUTE,
+       if (ps_sendmsg(ctx, PS_ROOT_FD(ctx), PS_ROUTE,
            (unsigned long)protocol, msg) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);

diff --git a/src/privsep-root.c b/src/privsep-root.c
index c635182129f2e0896d9b75a1f24510494f563b8c..eb2b3eef687a7319048d8c6d93ca14b03f20367b 100644 (file)
--- a/src/privsep-root.c
+++ b/src/privsep-root.c
@@ -97,7 +97,7 @@ ps_root_readerrorcb(void *arg, unsigned short events)
                goto out;                       \
        } while (0 /* CONSTCOND */)
 
-       len = readv(ctx->ps_root->psp_fd, iov, __arraycount(iov));
+       len = readv(PS_ROOT_FD(ctx), iov, __arraycount(iov));
        if (len == -1)
                PSR_ERROR(errno);
        else if ((size_t)len < sizeof(*psr_error))
@@ -115,14 +115,15 @@ ps_root_readerror(struct dhcpcd_ctx *ctx, void *data, size_t len)
            .psr_ctx = ctx,
            .psr_data = data, .psr_datalen = len,
        };
+       int fd = PS_ROOT_FD(ctx);
 
-       if (eloop_event_add(ctx->ps_eloop, ctx->ps_root->psp_fd, ELE_READ,
+       if (eloop_event_add(ctx->ps_eloop, fd, ELE_READ,
            ps_root_readerrorcb, &psr_ctx) == -1)
                return -1;
 
        eloop_enter(ctx->ps_eloop);
        eloop_start(ctx->ps_eloop, &ctx->sigset);
-       eloop_event_delete(ctx->ps_eloop, ctx->ps_root->psp_fd);
+       eloop_event_delete(ctx->ps_eloop, fd);
 
        errno = psr_ctx.psr_error.psr_errno;
        return psr_ctx.psr_error.psr_result;
@@ -145,8 +146,7 @@ ps_root_mreaderrorcb(void *arg, unsigned short events)
        if (events != ELE_READ)
                logerrx("%s: unexpected event 0x%04x", __func__, events);
 
-       len = recv(ctx->ps_root->psp_fd,
-           psr_error, sizeof(*psr_error), MSG_PEEK);
+       len = recv(PS_ROOT_FD(ctx), psr_error, sizeof(*psr_error), MSG_PEEK);
        if (len == -1)
                PSR_ERROR(errno);
        else if ((size_t)len < sizeof(*psr_error))
@@ -163,7 +163,7 @@ ps_root_mreaderrorcb(void *arg, unsigned short events)
                iov[1].iov_len = psr_ctx->psr_datalen;
        }
 
-       len = readv(ctx->ps_root->psp_fd, iov, __arraycount(iov));
+       len = readv(PS_ROOT_FD(ctx), iov, __arraycount(iov));
        if (len == -1)
                PSR_ERROR(errno);
        else if ((size_t)len != sizeof(*psr_error) + psr_ctx->psr_datalen)
@@ -180,14 +180,15 @@ ps_root_mreaderror(struct dhcpcd_ctx *ctx, void **data, size_t *len)
        struct psr_ctx psr_ctx = {
            .psr_ctx = ctx,
        };
+       int fd = PS_ROOT_FD(ctx);
 
-       if (eloop_event_add(ctx->ps_eloop, ctx->ps_root->psp_fd, ELE_READ,
+       if (eloop_event_add(ctx->ps_eloop, fd, ELE_READ,
            ps_root_mreaderrorcb, &psr_ctx) == -1)
                return -1;
 
        eloop_enter(ctx->ps_eloop);
        eloop_start(ctx->ps_eloop, &ctx->sigset);
-       eloop_event_delete(ctx->ps_eloop, ctx->ps_root->psp_fd);
+       eloop_event_delete(ctx->ps_eloop, fd);
 
        errno = psr_ctx.psr_error.psr_errno;
        *data = psr_ctx.psr_data;
@@ -210,12 +211,13 @@ ps_root_writeerror(struct dhcpcd_ctx *ctx, ssize_t result,
                { .iov_base = data, .iov_len = len },
        };
        ssize_t err;
+       int fd = PS_ROOT_FD(ctx);
 
 #ifdef PRIVSEP_DEBUG
        logdebugx("%s: result %zd errno %d", __func__, result, errno);
 #endif
 
-       err = writev(ctx->ps_root->psp_fd, iov, __arraycount(iov));
+       err = writev(fd, iov, __arraycount(iov));
 
        /* Error sending the message? Try sending the error of sending. */
        if (err == -1) {
@@ -225,7 +227,7 @@ ps_root_writeerror(struct dhcpcd_ctx *ctx, ssize_t result,
                psr.psr_errno = errno;
                iov[1].iov_base = NULL;
                iov[1].iov_len = 0;
-               err = writev(ctx->ps_root->psp_fd, iov, __arraycount(iov));
+               err = writev(fd, iov, __arraycount(iov));
        }
 
        return err;
@@ -960,13 +962,15 @@ ps_root_stop(struct dhcpcd_ctx *ctx)
         * log dhcpcd exits because the latter requires the former.
         * So we just log the intent to exit.
         * Even sending this will be a race to exit. */
-       logdebugx("%s%s%s will exit from PID %d",
-           psp->psp_ifname,
-           psp->psp_ifname[0] != '\0' ? ": " : "",
-           psp->psp_name, psp->psp_pid);
+       if (psp) {
+               logdebugx("%s%s%s will exit from PID %d",
+                   psp->psp_ifname,
+                   psp->psp_ifname[0] != '\0' ? ": " : "",
+                   psp->psp_name, psp->psp_pid);
 
-       if (ps_stopprocess(psp) == -1)
-               return -1;
+               if (ps_stopprocess(psp) == -1)
+                       return -1;
+       } /* else the root process has already exited :( */
 
        return ps_stopwait(ctx);
 }
@@ -978,7 +982,7 @@ ps_root_stopprocesses(struct dhcpcd_ctx *ctx)
        if (!(IN_PRIVSEP_SE(ctx)))
                return 0;
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_STOPPROCS, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_STOPPROCS, 0,
            NULL, 0) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -988,7 +992,7 @@ ssize_t
 ps_root_script(struct dhcpcd_ctx *ctx, const void *data, size_t len)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_SCRIPT,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_SCRIPT,
            0, data, len) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -998,7 +1002,7 @@ ssize_t
 ps_root_ioctl(struct dhcpcd_ctx *ctx, ioctl_request_t req, void *data,
     size_t len)
 {
-       int fd = ctx->ps_root->psp_fd;
+       int fd = PS_ROOT_FD(ctx);
 #ifdef IOCTL_REQUEST_TYPE
        unsigned long ulreq = 0;
 
@@ -1016,7 +1020,7 @@ ssize_t
 ps_root_unlink(struct dhcpcd_ctx *ctx, const char *file)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_UNLINK, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_UNLINK, 0,
            file, strlen(file) + 1) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -1026,7 +1030,7 @@ ssize_t
 ps_root_readfile(struct dhcpcd_ctx *ctx, const char *file,
     void *data, size_t len)
 {
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_READFILE, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_READFILE, 0,
            file, strlen(file) + 1) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
@@ -1047,7 +1051,7 @@ ps_root_writefile(struct dhcpcd_ctx *ctx, const char *file, mode_t mode,
        }
        memcpy(buf + flen, data, len);
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_WRITEFILE, mode,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_WRITEFILE, mode,
            buf, flen + len) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -1057,7 +1061,7 @@ ssize_t
 ps_root_filemtime(struct dhcpcd_ctx *ctx, const char *file, time_t *time)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_FILEMTIME, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_FILEMTIME, 0,
            file, strlen(file) + 1) == -1)
                return -1;
        return ps_root_readerror(ctx, time, sizeof(*time));
@@ -1067,7 +1071,7 @@ ssize_t
 ps_root_logreopen(struct dhcpcd_ctx *ctx)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_LOGREOPEN, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_LOGREOPEN, 0,
            NULL, 0) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -1084,7 +1088,7 @@ ps_root_getifaddrs(struct dhcpcd_ctx *ctx, struct ifaddrs **ifahead)
        size_t len;
        ssize_t err;
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx),
            PS_GETIFADDRS, 0, NULL, 0) == -1)
                return -1;
        err = ps_root_mreaderror(ctx, &buf, &len);
@@ -1159,7 +1163,7 @@ ssize_t
 ps_root_ip6forwarding(struct dhcpcd_ctx *ctx, const char *ifname)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_IP6FORWARDING, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_IP6FORWARDING, 0,
            ifname, ifname != NULL ? strlen(ifname) + 1 : 0) == -1)
                return -1;
        return ps_root_readerror(ctx, NULL, 0);
@@ -1171,7 +1175,7 @@ int
 ps_root_getauthrdm(struct dhcpcd_ctx *ctx, uint64_t *rdm)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_AUTH_MONORDM, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_AUTH_MONORDM, 0,
            rdm, sizeof(*rdm))== -1)
                return -1;
        return (int)ps_root_readerror(ctx, rdm, sizeof(*rdm));
@@ -1183,7 +1187,7 @@ int
 ps_root_dev_initialised(struct dhcpcd_ctx *ctx, const char *ifname)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_DEV_INITTED, 0,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_DEV_INITTED, 0,
            ifname, strlen(ifname) + 1)== -1)
                return -1;
        return (int)ps_root_readerror(ctx, NULL, 0);
@@ -1193,7 +1197,7 @@ int
 ps_root_dev_listening(struct dhcpcd_ctx * ctx)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root->psp_fd, PS_DEV_LISTENING,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_DEV_LISTENING,
            0, NULL, 0) == -1)
                return -1;
        return (int)ps_root_readerror(ctx, NULL, 0);

diff --git a/src/privsep-sun.c b/src/privsep-sun.c
index a4794aaa9dc3a9e809e26046da56876f1dc22049..a645d15dc25226ff5846a554afd06dd116a15e71 100644 (file)
--- a/src/privsep-sun.c
+++ b/src/privsep-sun.c
@@ -105,7 +105,7 @@ ssize_t
 ps_root_ioctl6(struct dhcpcd_ctx *ctx, unsigned long request, void *data, size_t len)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root_fd, PS_IOCTL6,
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_IOCTL6,
            request, data, len) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
@@ -115,7 +115,7 @@ ssize_t
 ps_root_route(struct dhcpcd_ctx *ctx, void *data, size_t len)
 {
 
-       if (ps_sendcmd(ctx, ctx->ps_root_fd, PS_ROUTE, 0, data, len) == -1)
+       if (ps_sendcmd(ctx, PS_ROOT_FD(ctx), PS_ROUTE, 0, data, len) == -1)
                return -1;
        return ps_root_readerror(ctx, data, len);
 }

diff --git a/src/privsep.h b/src/privsep.h
index f03b2be76062d71fb02e4fcc9723299835e11a94..34d18dcf7b503f7f0ee342414030c77b739907de 100644 (file)
--- a/src/privsep.h
+++ b/src/privsep.h
@@ -113,6 +113,8 @@
 #define PRIVSEP_RIGHTS
 #endif
 
+#define PS_ROOT_FD(ctx) ((ctx)->ps_root ? (ctx)->ps_root->psp_fd : -1)
+
 #ifdef __linux__
 # include <linux/version.h>
 # if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 5, 0)