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Cosmetic changes to packet.c.

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This commit is contained in:
Nicholas J. Kain 2011-06-27 13:01:39 -04:00
parent 55f24fd2a3
commit b72b551a0d
1 changed files with 15 additions and 24 deletions
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39
ndhc/packet.c
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@ -47,8 +47,8 @@
#include "options.h" #include "options.h"
#include "strl.h" #include "strl.h"
/* Returns fd of new listen socket bound to @ip:@port on interface @inf // Returns fd of new listen socket bound to @ip:@port on interface @inf
* on success, or -1 on failure. */ // on success, or -1 on failure.
static int create_udp_listen_socket(unsigned int ip, int port, char *inf) static int create_udp_listen_socket(unsigned int ip, int port, char *inf)
{ {
log_line("Opening listen socket on 0x%08x:%d %s", ip, port, inf); log_line("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
@ -540,7 +540,7 @@ static void dhcp_ack_or_nak_packet(struct client_state_t *cs,
} else { } else {
memcpy(&cs->lease, temp, 4); memcpy(&cs->lease, temp, 4);
cs->lease = ntohl(cs->lease); cs->lease = ntohl(cs->lease);
/* Enforce upper and lower bounds on lease. */ // Enforce upper and lower bounds on lease.
cs->lease &= 0x0fffffff; cs->lease &= 0x0fffffff;
if (cs->lease < RETRY_DELAY) if (cs->lease < RETRY_DELAY)
cs->lease = RETRY_DELAY; cs->lease = RETRY_DELAY;
@ -581,7 +581,7 @@ void handle_packet(struct client_state_t *cs)
len = get_packet(&packet, cs->listenFd); len = get_packet(&packet, cs->listenFd);
else if (cs->listenMode == LM_RAW) else if (cs->listenMode == LM_RAW)
len = get_raw_packet(&packet, cs->listenFd); len = get_raw_packet(&packet, cs->listenFd);
else /* LM_NONE */ else // LM_NONE
return; return;
if (len < 0) { if (len < 0) {
@ -636,7 +636,7 @@ void handle_packet(struct client_state_t *cs)
} }
} }
/* Create a random xid */ // Generate a 32-bit pseudorandom number
uint32_t random_xid(void) uint32_t random_xid(void)
{ {
static int initialized; static int initialized;
@ -662,7 +662,7 @@ uint32_t random_xid(void)
return rand(); return rand();
} }
/* initialize a packet with the proper defaults */ // Initialize a DHCP client packet that will be sent to a server
static struct dhcpmsg init_packet(char type, uint32_t xid) static struct dhcpmsg init_packet(char type, uint32_t xid)
{ {
struct dhcpmsg packet = { struct dhcpmsg packet = {
@ -687,42 +687,37 @@ static struct dhcpmsg init_packet(char type, uint32_t xid)
return packet; return packet;
} }
/* Broadcast a DHCP discover packet to the network, with an optionally // Broadcast a DHCP discover packet to the network, with an optionally
* requested IP */ // requested IP
int send_discover(uint32_t xid, uint32_t requested) int send_discover(uint32_t xid, uint32_t requested)
{ {
struct dhcpmsg packet = init_packet(DHCPDISCOVER, xid); struct dhcpmsg packet = init_packet(DHCPDISCOVER, xid);
if (requested) if (requested)
add_u32_option(&packet, DHCP_REQUESTED_IP, requested); add_u32_option(&packet, DHCP_REQUESTED_IP, requested);
// Request a RFC-specified max size to work around buggy servers.
/* Request a RFC-specified max size to work around buggy servers. */
add_u32_option(&packet, DHCP_MAX_SIZE, htons(576)); add_u32_option(&packet, DHCP_MAX_SIZE, htons(576));
add_option_request_list(&packet); add_option_request_list(&packet);
log_line("Sending discover..."); log_line("Sending discover...");
return send_dhcp_raw(&packet); return send_dhcp_raw(&packet);
} }
/* Broadcasts a DHCP request message */ // Broadcasts a DHCP request message
int send_selecting(uint32_t xid, uint32_t server, uint32_t requested) int send_selecting(uint32_t xid, uint32_t server, uint32_t requested)
{ {
struct dhcpmsg packet = init_packet(DHCPREQUEST, xid); struct dhcpmsg packet = init_packet(DHCPREQUEST, xid);
struct in_addr addr;
add_u32_option(&packet, DHCP_REQUESTED_IP, requested); add_u32_option(&packet, DHCP_REQUESTED_IP, requested);
add_u32_option(&packet, DHCP_SERVER_ID, server); add_u32_option(&packet, DHCP_SERVER_ID, server);
add_option_request_list(&packet); add_option_request_list(&packet);
addr.s_addr = requested; struct in_addr addr = { .s_addr = requested };
log_line("Sending select for %s...", inet_ntoa(addr)); log_line("Sending select for %s...", inet_ntoa(addr));
return send_dhcp_raw(&packet); return send_dhcp_raw(&packet);
} }
/* Unicasts or broadcasts a DHCP renew message */ // Unicasts or broadcasts a DHCP renew message
int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr) int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr)
{ {
struct dhcpmsg packet = init_packet(DHCPREQUEST, xid); struct dhcpmsg packet = init_packet(DHCPREQUEST, xid);
packet.ciaddr = ciaddr; packet.ciaddr = ciaddr;
add_option_request_list(&packet); add_option_request_list(&packet);
log_line("Sending renew..."); log_line("Sending renew...");
if (server) if (server)
@ -731,28 +726,24 @@ int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr)
return send_dhcp_raw(&packet); return send_dhcp_raw(&packet);
} }
/* Broadcast a DHCP decline message */ // Broadcast a DHCP decline message
int send_decline(uint32_t xid, uint32_t server, uint32_t requested) int send_decline(uint32_t xid, uint32_t server, uint32_t requested)
{ {
struct dhcpmsg packet = init_packet(DHCPDECLINE, xid); struct dhcpmsg packet = init_packet(DHCPDECLINE, xid);
// DHCPDECLINE uses "requested ip", not ciaddr, to store offered IP
/* DHCPDECLINE uses "requested ip", not ciaddr, to store offered IP */
add_u32_option(&packet, DHCP_REQUESTED_IP, requested); add_u32_option(&packet, DHCP_REQUESTED_IP, requested);
add_u32_option(&packet, DHCP_SERVER_ID, server); add_u32_option(&packet, DHCP_SERVER_ID, server);
log_line("Sending decline..."); log_line("Sending decline...");
return send_dhcp_raw(&packet); return send_dhcp_raw(&packet);
} }
/* Unicasts a DHCP release message */ // Unicasts a DHCP release message
int send_release(uint32_t server, uint32_t ciaddr) int send_release(uint32_t server, uint32_t ciaddr)
{ {
struct dhcpmsg packet = init_packet(DHCPRELEASE, random_xid()); struct dhcpmsg packet = init_packet(DHCPRELEASE, random_xid());
packet.ciaddr = ciaddr; packet.ciaddr = ciaddr;
add_u32_option(&packet, DHCP_REQUESTED_IP, ciaddr); add_u32_option(&packet, DHCP_REQUESTED_IP, ciaddr);
add_u32_option(&packet, DHCP_SERVER_ID, server); add_u32_option(&packet, DHCP_SERVER_ID, server);
log_line("Sending release..."); log_line("Sending release...");
return send_dhcp_cooked(&packet, ciaddr, server); return send_dhcp_cooked(&packet, ciaddr, server);
} }