dhcpc: export unrecognized options in "optNN=XXXXXXXXX" form

function                                             old     new   delta
udhcp_run_script                                     609     818    +209

Signed-off-by: Nigel Hathaway <Nigel.Hathaway@ubiquisys.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 47 insertions, 10 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index ca82d37e6..510c3a1d0 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -300,6 +300,14 @@ static char **fill_envp(struct dhcp_packet *packet)
         uint8_t *temp;
         uint8_t overload = 0;
 
+#define BITMAP unsigned
+#define BBITS (sizeof(BITMAP) * 8)
+#define BMASK(i) (1 << (i & (sizeof(BITMAP) * 8 - 1)))
+#define FOUND_OPTS(i) (found_opts[(unsigned)i / BBITS])
+        BITMAP found_opts[256 / BBITS];
+
+        memset(found_opts, 0, sizeof(found_opts));
+
         /* We need 6 elements for:
          * "interface=IFACE"
          * "ip=N.N.N.N" from packet->yiaddr
@@ -311,18 +319,21 @@ static char **fill_envp(struct dhcp_packet *packet)
         envc = 6;
         /* +1 element for each option, +2 for subnet option: */
         if (packet) {
-                for (i = 0; dhcp_optflags[i].code; i++) {
-                        if (udhcp_get_option(packet, dhcp_optflags[i].code)) {
-                                if (dhcp_optflags[i].code == DHCP_SUBNET)
+                /* note: do not search for "pad" (0) and "end" (255) options */
+                for (i = 1; i < 255; i++) {
+                        temp = udhcp_get_option(packet, i);
+                        if (temp) {
+                                if (i == DHCP_OPTION_OVERLOAD)
+                                        overload = *temp;
+                                else if (i == DHCP_SUBNET)
                                         envc++; /* for mton */
                                 envc++;
+                                /*if (i != DHCP_MESSAGE_TYPE)*/
+                                FOUND_OPTS(i) |= BMASK(i);
                         }
                 }
-                temp = udhcp_get_option(packet, DHCP_OPTION_OVERLOAD);
-                if (temp)
-                        overload = *temp;
         }
-        curr = envp = xzalloc(sizeof(char *) * envc);
+        curr = envp = xzalloc(sizeof(envp[0]) * envc);
 
         *curr = xasprintf("interface=%s", client_config.interface);
         putenv(*curr++);
@@ -337,12 +348,16 @@ static char **fill_envp(struct dhcp_packet *packet)
         opt_name = dhcp_option_strings;
         i = 0;
         while (*opt_name) {
-                temp = udhcp_get_option(packet, dhcp_optflags[i].code);
-                if (!temp)
+                uint8_t code = dhcp_optflags[i].code;
+                BITMAP *found_ptr = &FOUND_OPTS(code);
+                BITMAP found_mask = BMASK(code);
+                if (!(*found_ptr & found_mask))
                         goto next;
+                *found_ptr &= ~found_mask; /* leave only unknown options */
+                temp = udhcp_get_option(packet, code);
                 *curr = xmalloc_optname_optval(temp, &dhcp_optflags[i], opt_name);
                 putenv(*curr++);
-                if (dhcp_optflags[i].code == DHCP_SUBNET) {
+                if (code == DHCP_SUBNET) {
                         /* Subnet option: make things like "$ip/$mask" possible */
                         uint32_t subnet;
                         move_from_unaligned32(subnet, temp);
@@ -368,6 +383,28 @@ static char **fill_envp(struct dhcp_packet *packet)
                 *curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
                 putenv(*curr++);
         }
+        /* Handle unknown options */
+        for (i = 0; i < 256;) {
+                BITMAP bitmap = FOUND_OPTS(i);
+                if (!bitmap) {
+                        i += BBITS;
+                        continue;
+                }
+                if (bitmap & BMASK(i)) {
+                        unsigned len, ofs;
+
+                        temp = udhcp_get_option(packet, i);
+                        /* udhcp_get_option returns ptr to data portion,
+                         * need to go back to get len
+                         */
+                        len = temp[-OPT_DATA + OPT_LEN];
+                        *curr = xmalloc(sizeof("optNNN=") + 1 + len*2);
+                        ofs = sprintf(*curr, "opt%u=", i);
+                        bin2hex(*curr + ofs, (void*) temp, len)[0] = '\0';
+                        putenv(*curr++);
+                }
+                i++;
+        }
         return envp;
 }