Thank you for applying the commits!
I started implementing support for RFC 3396, hopefully it will be ready
soon.
Martin
On Mon, 29 Jun 2020 at 08:40, Denys Vlasenko
wrote:
> Applied, thanks
>
> On Tue, Jun 23, 2020 at 3:41 PM Martin Lewis
> wrote:
> >
> > fill_envp now iterates over the packet only once instead of a few
> hundred times
> > using the new option scanner.
> >
> > Signed-off-by: Martin Lewis
> > ---
> > networking/udhcp/dhcpc.c | 201
> ---
> > 1 file changed, 87 insertions(+), 114 deletions(-)
> >
> > diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
> > index 102178a4f..2669428e1 100644
> > --- a/networking/udhcp/dhcpc.c
> > +++ b/networking/udhcp/dhcpc.c
> > @@ -386,59 +386,81 @@ static NOINLINE char
> *xmalloc_optname_optval(uint8_t *option, const struct dhcp_
> > return ret;
> > }
> >
> > +static void putenvp(llist_t **envp, char *new_opt)
> > +{
> > + putenv(new_opt);
> > + llist_add_to(envp, new_opt);
> > +}
> > +
> > +static int is_unknown_opt(uint8_t code, const struct dhcp_optflag **dh,
> const char **opt_name)
> > +{
> > +*opt_name = "";
> > +
> > +/* Find the option:
> > + * dhcp_optflags is sorted so we stop searching when dh->code >=
> code, which is faster
> > + * than iterating over the entire array.
> > + * Options which don't have a match in dhcp_option_strings[], e.g
> DHCP_REQUESTED_IP,
> > + * are located after the sorted array, so these entries will never
> be reached
> > + * and they'll count as unknown options.
> > + */
> > +for (*dh = dhcp_optflags; (*dh)->code && (*dh)->code < code;
> (*dh)++);
> > +
> > +if ((*dh)->code == code)
> > +*opt_name = nth_string(dhcp_option_strings, (*dh -
> dhcp_optflags));
> > +
> > +return (*dh)->code > code;
> > +}
> > +
> > /* put all the parameters into the environment */
> > -static char **fill_envp(struct dhcp_packet *packet)
> > +static llist_t *fill_envp(struct dhcp_packet *packet)
> > {
> > - int envc;
> > - int i;
> > - char **envp, **curr;
> > - const char *opt_name;
> > - 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 7 elements for:
> > -* "interface=IFACE"
> > -* "ip=N.N.N.N" from packet->yiaddr
> > -* "giaddr=IP" from packet->gateway_nip (unless 0)
> > -* "siaddr=IP" from packet->siaddr_nip (unless 0)
> > -* "boot_file=FILE" from packet->file (unless overloaded)
> > -* "sname=SERVER_HOSTNAME" from packet->sname (unless overloaded)
> > -* terminating NULL
> > -*/
> > - envc = 7;
> > - /* +1 element for each option, +2 for subnet option: */
> > - if (packet) {
> > - /* note: do not search for "pad" (0) and "end" (255)
> options */
> > -//TODO: change logic to scan packet _once_
> > - 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 $mask */
> > - envc++;
> > - /*if (i != DHCP_MESSAGE_TYPE)*/
> > - FOUND_OPTS(i) |= BMASK(i);
> > - }
> > - }
> > - }
> > - curr = envp = xzalloc(sizeof(envp[0]) * envc);
> > + char *new_opt;
> > + uint8_t *optptr;
> > + const struct dhcp_optflag *dh;
> > + struct dhcp_scan_state scan_state;
> > + const char *opt_name = "";
> > + llist_t *envp = NULL;
> >
> > - *curr = xasprintf("interface=%s", client_data.interface);
> > - putenv(*curr++);
> > + new_opt = xasprintf("interface=%s", client_data.interface);
> > + putenvp(, new_opt);
> >
> > if (!packet)
> > return envp;
> >
> > + init_scan_state(packet, _state);
> > +
> > +/* Iterate over the packet options.
> > + * Handle each option based on whether it's an unknown / known
> option.
> > + * There may be (although unlikely) duplicate options. For now,
> only the last
> > + * appearing option will be stored in the environment, and all
> duplicates
> > + * are freed properly.
> > + * Long options may be implemented in the future (see RFC 3396) if
> needed.
> > + */
> > + while ((optptr = udhcp_scan_options(packet, _state)) !=
> NULL) {
> > +
