Add --ip=dhcp and --ip6=dhcp options

Currently, --ip=dhcp is equivalent to --ip=none
and --ip6=dhcp does nothing either, except for parsing correctly

3 files changed, 37 insertions, 22 deletions

diff --git a/src/firejail/firejail.h b/src/firejail/firejail.h
index 03bcbda46..a5eeb4067 100644
--- a/src/firejail/firejail.h
+++ b/src/firejail/firejail.h
@@ -103,6 +103,8 @@ typedef struct bridge_t {
 
         // flags
         uint8_t arg_ip_none;    // --ip=none
+  uint8_t arg_ip_dhcp;
+  uint8_t arg_ip6_dhcp;
         uint8_t macvlan;        // set by --net=eth0 (or eth1, ...); reset by --net=br0 (or br1, ...)
         uint8_t configured;
         uint8_t scan;           // set by --scan
diff --git a/src/firejail/main.c b/src/firejail/main.c
index 179f8ddf9..0b9ebc482 100644
--- a/src/firejail/main.c
+++ b/src/firejail/main.c
@@ -2144,7 +2144,10 @@ int main(int argc, char **argv) {
                                 // configure this IP address for the last bridge defined
                                 if (strcmp(argv[i] + 5, "none") == 0)
                                         br->arg_ip_none = 1;
-                                else {
+                                else if (strcmp(argv[i] + 5, "dhcp") == 0) {
+                                        br->arg_ip_none = 1;
+                                        br->arg_ip_dhcp = 1;
+                                } else {
                                         if (atoip(argv[i] + 5, &br->ipsandbox)) {
                                                 fprintf(stderr, "Error: invalid IP address\n");
                                                 exit(1);
@@ -2184,20 +2187,24 @@ int main(int argc, char **argv) {
                                         fprintf(stderr, "Error: no network device configured\n");
                                         exit(1);
                                 }
-                                if (br->ip6sandbox) {
+                                if (br->arg_ip6_dhcp || br->ip6sandbox) {
                                         fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
                                         exit(1);
                                 }
 
                                 // configure this IP address for the last bridge defined
-                                if (check_ip46_address(argv[i] + 6) == 0) {
-                                        fprintf(stderr, "Error: invalid IPv6 address\n");
-                                        exit(1);
-                                }
-
-                                br->ip6sandbox = strdup(argv[i] + 6);
-                                if (br->ip6sandbox == NULL)
-                                        errExit("strdup");
+        if (strcmp(argv[i] + 6, "dhcp") == 0)
+          br->arg_ip6_dhcp = 1;
+        else {
+          if (check_ip46_address(argv[i] + 6) == 0) {
+            fprintf(stderr, "Error: invalid IPv6 address\n");
+            exit(1);
+          }
+
+          br->ip6sandbox = strdup(argv[i] + 6);
+          if (br->ip6sandbox == NULL)
+            errExit("strdup");
+        }
                         }
                         else
                                 exit_err_feature("networking");
diff --git a/src/firejail/profile.c b/src/firejail/profile.c
index 9a724331b..959678501 100644
--- a/src/firejail/profile.c
+++ b/src/firejail/profile.c
@@ -672,7 +672,10 @@ int profile_check_line(char *ptr, int lineno, const char *fname) {
                         // configure this IP address for the last bridge defined
                         if (strcmp(ptr + 3, "none") == 0)
                                 br->arg_ip_none = 1;
-                        else {
+                        else if (strcmp(ptr + 3, "dhcp") == 0) {
+                                br->arg_ip_none = 1;
+                                br->arg_ip_dhcp = 1;
+                        } else {
                                 if (atoip(ptr + 3, &br->ipsandbox)) {
                                         fprintf(stderr, "Error: invalid IP address\n");
                                         exit(1);
@@ -693,21 +696,24 @@ int profile_check_line(char *ptr, int lineno, const char *fname) {
                                 fprintf(stderr, "Error: no network device configured\n");
                                 exit(1);
                         }
-                        if (br->ip6sandbox) {
+                        if (br->arg_ip6_dhcp || br->ip6sandbox) {
                                 fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
                                 exit(1);
                         }
 
-                        // configure this IP address for the last bridge defined
-                        if (check_ip46_address(ptr + 4) == 0) {
-                                fprintf(stderr, "Error: invalid IPv6 address\n");
-                                exit(1);
-                        }
-
-                        br->ip6sandbox = strdup(ptr + 4);
-                        if (br->ip6sandbox == NULL)
-                                errExit("strdup");
-
+      // configure this IP address for the last bridge defined
+      if (strcmp(ptr + 4, "dhcp") == 0)
+        br->arg_ip6_dhcp = 1;
+      else {
+        if (check_ip46_address(ptr + 4) == 0) {
+          fprintf(stderr, "Error: invalid IPv6 address\n");
+          exit(1);
+        }
+
+        br->ip6sandbox = strdup(ptr + 4);
+        if (br->ip6sandbox == NULL)
+          errExit("strdup");
+      }
                 }
                 else
                         warning_feature_disabled("networking");