diff options
| -rw-r--r-- | lib/Kconfig | 3 | ||||
| -rw-r--r-- | net/bootp.c | 68 |
2 files changed, 54 insertions, 17 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index 189e6eb31aa..9b62b3bbea7 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -265,7 +265,8 @@ config REGEX choice prompt "Pseudo-random library support type" depends on NET_RANDOM_ETHADDR || RANDOM_UUID || CMD_UUID || \ - RNG_SANDBOX || UT_LIB && AES || FAT_WRITE + RNG_SANDBOX || UT_LIB && AES || FAT_WRITE || CMD_BOOTP || \ + CMD_DHCP || CMD_DHCP6 default LIB_RAND help Select the library to provide pseudo-random number generator diff --git a/net/bootp.c b/net/bootp.c index b9e3cccb4f9..c34ffe27854 100644 --- a/net/bootp.c +++ b/net/bootp.c @@ -42,6 +42,22 @@ */ #define TIMEOUT_MS ((3 + (CONFIG_NET_RETRY_COUNT * 5)) * 1000) +/* + * According to rfc951 : 7.2. Client Retransmission Strategy + * "After the 'average' backoff reaches about 60 seconds, it should be + * increased no further, but still randomized." + * + * U-Boot has saturated this backoff at 2 seconds for a long time. + * To modify, set the environment variable "bootpretransmitperiodmax" + */ +#define RETRANSMIT_PERIOD_MAX_MS 60000 + +/* Retransmission timeout for the initial packet (in milliseconds). + * This timeout will double on each retry. To modify, set the + * environment variable bootpretransmitperiodinit. + */ +#define RETRANSMIT_PERIOD_INIT_MS 250 + #ifndef CFG_DHCP_MIN_EXT_LEN /* minimal length of extension list */ #define CFG_DHCP_MIN_EXT_LEN 64 #endif @@ -53,6 +69,7 @@ u32 bootp_ids[CFG_BOOTP_ID_CACHE_SIZE]; unsigned int bootp_num_ids; int bootp_try; +u32 bootp_id; ulong bootp_start; ulong bootp_timeout; char net_nis_domain[32] = {0,}; /* Our NIS domain */ @@ -60,6 +77,7 @@ char net_hostname[32] = {0,}; /* Our hostname */ char net_root_path[CONFIG_BOOTP_MAX_ROOT_PATH_LEN] = {0,}; /* Our bootpath */ static ulong time_taken_max; +static u32 retransmit_period_max_ms; #if defined(CONFIG_CMD_DHCP) static dhcp_state_t dhcp_state = INIT; @@ -396,6 +414,7 @@ static void bootp_handler(uchar *pkt, unsigned dest, struct in_addr sip, static void bootp_timeout_handler(void) { ulong time_taken = get_timer(bootp_start); + int rand_minus_plus_100; if (time_taken >= time_taken_max) { #ifdef CONFIG_BOOTP_MAY_FAIL @@ -414,8 +433,17 @@ static void bootp_timeout_handler(void) } } else { bootp_timeout *= 2; - if (bootp_timeout > 2000) - bootp_timeout = 2000; + if (bootp_timeout > retransmit_period_max_ms) + bootp_timeout = retransmit_period_max_ms; + + /* Randomize by adding bootp_timeout*RAND, where RAND + * is a randomization factor between -0.1..+0.1 + */ + srand(get_ticks() + rand()); + rand_minus_plus_100 = ((rand() % 200) - 100); + bootp_timeout = bootp_timeout + + (((int)bootp_timeout * rand_minus_plus_100) / 1000); + net_set_timeout_handler(bootp_timeout, bootp_timeout_handler); bootp_request(); } @@ -714,7 +742,8 @@ void bootp_reset(void) bootp_num_ids = 0; bootp_try = 0; bootp_start = get_timer(0); - bootp_timeout = 250; + + bootp_timeout = env_get_ulong("bootpretransmitperiodinit", 10, RETRANSMIT_PERIOD_INIT_MS); } void bootp_request(void) @@ -726,7 +755,6 @@ void bootp_request(void) #ifdef CONFIG_BOOTP_RANDOM_DELAY ulong rand_ms; #endif - u32 bootp_id; struct in_addr zero_ip; struct in_addr bcast_ip; char *ep; /* Environment pointer */ @@ -742,6 +770,9 @@ void bootp_request(void) else time_taken_max = TIMEOUT_MS; + retransmit_period_max_ms = env_get_ulong("bootpretransmitperiodmax", 10, + RETRANSMIT_PERIOD_MAX_MS); + #ifdef CONFIG_BOOTP_RANDOM_DELAY /* Random BOOTP delay */ if (bootp_try == 0) srand_mac(); @@ -801,18 +832,23 @@ void bootp_request(void) extlen = bootp_extended((u8 *)bp->bp_vend); #endif - /* - * Bootp ID is the lower 4 bytes of our ethernet address - * plus the current time in ms. - */ - bootp_id = ((u32)net_ethaddr[2] << 24) - | ((u32)net_ethaddr[3] << 16) - | ((u32)net_ethaddr[4] << 8) - | (u32)net_ethaddr[5]; - bootp_id += get_timer(0); - bootp_id = htonl(bootp_id); - bootp_add_id(bootp_id); - net_copy_u32(&bp->bp_id, &bootp_id); + /* Only generate a new transaction ID for each new BOOTP request */ + if (bootp_try == 1) { + /* + * Bootp ID is the lower 4 bytes of our ethernet address + * plus the current time in ms. + */ + bootp_id = ((u32)net_ethaddr[2] << 24) + | ((u32)net_ethaddr[3] << 16) + | ((u32)net_ethaddr[4] << 8) + | (u32)net_ethaddr[5]; + bootp_id += get_timer(0); + bootp_id = htonl(bootp_id); + bootp_add_id(bootp_id); + net_copy_u32(&bp->bp_id, &bootp_id); + } else { + net_copy_u32(&bp->bp_id, &bootp_id); + } /* * Calculate proper packet lengths taking into account the |