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| author | Vladislav Grishenko <themiron@mail.ru> | 2010-10-17 12:27:50 +0200 |
|---|---|---|
| committer | Denys Vlasenko <vda.linux@googlemail.com> | 2010-10-17 12:27:50 +0200 |
| commit | ad8def2d8ad980a5b759c32a220828ea1248e5b6 (patch) | |
| tree | fdb7ed18d48a2957fc5f7481a07e60b78efab042 | |
| parent | cfe114c4f3d4e1dfc00196d8df316874eaf2d2b8 (diff) | |
| download | busybox-ad8def2d8ad980a5b759c32a220828ea1248e5b6.tar.gz | |
udhcpc: fix OPTION_IP_PAIR parsing
http://git.busybox.net/busybox/commit/?id=7d3a48a003cd645edfae2b404493688022
revealed incorrect OPTION_IP_PAIR implementation, which doesn't respect
option length and causes erroneous classful routes, composed from garbage
or first bytes from the next DHCP packet option.
Signed-off-by: Vladislav Grishenko <themiron@mail.ru>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
| -rw-r--r-- | networking/udhcp/dhcpc.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c index de1b79844..27d6ad1a8 100644 --- a/networking/udhcp/dhcpc.c +++ b/networking/udhcp/dhcpc.c @@ -89,6 +89,7 @@ static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_ /* option points to OPT_DATA, need to go back and get OPT_LEN */ len = option[OPT_LEN - OPT_DATA]; + type = optflag->flags & OPTION_TYPE_MASK; optlen = dhcp_option_lengths[type]; upper_length = len_of_option_as_string[type] * ((unsigned)len / (unsigned)optlen); @@ -97,17 +98,16 @@ static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_ dest += sprintf(ret, "%s=", opt_name); while (len >= optlen) { + unsigned ip_ofs = 0; + switch (type) { case OPTION_IP_PAIR: dest += sprint_nip(dest, "", option); *dest++ = '/'; - option += 4; - optlen = 4; + ip_ofs = 4; + /* fall through */ case OPTION_IP: - dest += sprint_nip(dest, "", option); -// TODO: it can be a list only if (optflag->flags & OPTION_LIST). -// Should we bail out/warn if we see multi-ip option which is -// not allowed to be such? For example, DHCP_BROADCAST... + dest += sprint_nip(dest, "", option + ip_ofs); break; // case OPTION_BOOLEAN: // dest += sprintf(dest, *option ? "yes" : "no"); @@ -218,7 +218,10 @@ static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_ } /* switch */ option += optlen; len -= optlen; - if (len <= 0) +// TODO: it can be a list only if (optflag->flags & OPTION_LIST). +// Should we bail out/warn if we see multi-ip option which is +// not allowed to be such (for example, DHCP_BROADCAST)? - + if (len <= 0 /* || !(optflag->flags & OPTION_LIST) */) break; *dest++ = ' '; *dest = '\0'; |