diff options
Diffstat (limited to 'release/src/router/busybox/networking/udhcp/files.c')
-rw-r--r-- | release/src/router/busybox/networking/udhcp/files.c | 568 |
1 files changed, 357 insertions, 211 deletions
diff --git a/release/src/router/busybox/networking/udhcp/files.c b/release/src/router/busybox/networking/udhcp/files.c index 3d0344b0..55f35978 100644 --- a/release/src/router/busybox/networking/udhcp/files.c +++ b/release/src/router/busybox/networking/udhcp/files.c @@ -1,287 +1,433 @@ -/* +/* vi: set sw=4 ts=4: */ +/* * files.c -- DHCP server file manipulation * * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001 + * + * Licensed under GPLv2, see file LICENSE in this tarball for details. */ - -#include <sys/socket.h> -#include <arpa/inet.h> -#include <string.h> -#include <stdlib.h> -#include <time.h> -#include <ctype.h> +#include <netinet/ether.h> + +#include "common.h" #include "dhcpd.h" -#include "files.h" #include "options.h" -#include "common.h" -/* on these functions, make sure you datatype matches */ +#if BB_LITTLE_ENDIAN +static inline uint64_t hton64(uint64_t v) +{ + return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32); +} +#else +#define hton64(v) (v) +#endif +#define ntoh64(v) hton64(v) + + +/* on these functions, make sure your datatype matches */ static int read_ip(const char *line, void *arg) { - struct in_addr *addr = arg; - struct hostent *host; - int retval = 1; - - if (!inet_aton(line, addr)) { - if ((host = gethostbyname(line))) - addr->s_addr = *((unsigned long *) host->h_addr_list[0]); - else retval = 0; - } - return retval; + len_and_sockaddr *lsa; + + lsa = host_and_af2sockaddr(line, 0, AF_INET); + if (!lsa) + return 0; + *(uint32_t*)arg = lsa->u.sin.sin_addr.s_addr; + free(lsa); + return 1; +} + + +static int read_mac(const char *line, void *arg) +{ + return NULL == ether_aton_r(line, (struct ether_addr *)arg); } static int read_str(const char *line, void *arg) { char **dest = arg; - - if (*dest) free(*dest); - *dest = strdup(line); - + + free(*dest); + *dest = xstrdup(line); return 1; } static int read_u32(const char *line, void *arg) { - u_int32_t *dest = arg; - char *endptr; - *dest = strtoul(line, &endptr, 0); - return endptr[0] == '\0'; + *(uint32_t*)arg = bb_strtou32(line, NULL, 10); + return errno == 0; } static int read_yn(const char *line, void *arg) { char *dest = arg; - int retval = 1; - if (!strcasecmp("yes", line)) + if (!strcasecmp("yes", line)) { *dest = 1; - else if (!strcasecmp("no", line)) + return 1; + } + if (!strcasecmp("no", line)) { *dest = 0; - else retval = 0; - - return retval; + return 1; + } + return 0; +} + + +/* find option 'code' in opt_list */ +struct option_set* FAST_FUNC find_option(struct option_set *opt_list, uint8_t code) +{ + while (opt_list && opt_list->data[OPT_CODE] < code) + opt_list = opt_list->next; + + if (opt_list && opt_list->data[OPT_CODE] == code) + return opt_list; + return NULL; +} + + +/* add an option to the opt_list */ +static void attach_option(struct option_set **opt_list, + const struct dhcp_option *option, char *buffer, int length) +{ + struct option_set *existing, *new, **curr; + + existing = find_option(*opt_list, option->code); + if (!existing) { + DEBUG("Attaching option %02x to list", option->code); + +#if ENABLE_FEATURE_UDHCP_RFC3397 + if ((option->flags & TYPE_MASK) == OPTION_STR1035) + /* reuse buffer and length for RFC1035-formatted string */ + buffer = (char *)dname_enc(NULL, 0, buffer, &length); +#endif + + /* make a new option */ + new = xmalloc(sizeof(*new)); + new->data = xmalloc(length + 2); + new->data[OPT_CODE] = option->code; + new->data[OPT_LEN] = length; + memcpy(new->data + 2, buffer, length); + + curr = opt_list; + while (*curr && (*curr)->data[OPT_CODE] < option->code) + curr = &(*curr)->next; + + new->next = *curr; + *curr = new; +#if ENABLE_FEATURE_UDHCP_RFC3397 + if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL) + free(buffer); +#endif + return; + } + + /* add it to an existing option */ + DEBUG("Attaching option %02x to existing member of list", option->code); + if (option->flags & OPTION_LIST) { +#if ENABLE_FEATURE_UDHCP_RFC3397 + if ((option->flags & TYPE_MASK) == OPTION_STR1035) + /* reuse buffer and length for RFC1035-formatted string */ + buffer = (char *)dname_enc(existing->data + 2, + existing->data[OPT_LEN], buffer, &length); +#endif + if (existing->data[OPT_LEN] + length <= 255) { + existing->data = xrealloc(existing->data, + existing->data[OPT_LEN] + length + 3); + if ((option->flags & TYPE_MASK) == OPTION_STRING) { + /* ' ' can bring us to 256 - bad */ + if (existing->data[OPT_LEN] + length >= 255) + return; + /* add space separator between STRING options in a list */ + existing->data[existing->data[OPT_LEN] + 2] = ' '; + existing->data[OPT_LEN]++; + } + memcpy(existing->data + existing->data[OPT_LEN] + 2, buffer, length); + existing->data[OPT_LEN] += length; + } /* else, ignore the data, we could put this in a second option in the future */ +#if ENABLE_FEATURE_UDHCP_RFC3397 + if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL) + free(buffer); +#endif + } /* else, ignore the new data */ } -#define READ_CONFIG_BUF_SIZE 512 /* domainname may have 254 chars */ /* read a dhcp option and add it to opt_list */ static int read_opt(const char *const_line, void *arg) { - char line[READ_CONFIG_BUF_SIZE]; struct option_set **opt_list = arg; char *opt, *val, *endptr; - struct dhcp_option *option; - int retval = 0, length; - char buffer[256]; /* max opt length */ - u_int16_t result_u16; - u_int32_t result_u32; - void *valptr; - - if ((opt = strtok(strcpy(line, const_line), " \t="))) { - - for (option = options; option->code; option++) - if (!strcasecmp(option->name, opt)) - break; - - if (option->code) do { + char *line; + const struct dhcp_option *option; + int retval, length, idx; + char buffer[8] ALIGNED(4); + uint16_t *result_u16 = (uint16_t *) buffer; + uint32_t *result_u32 = (uint32_t *) buffer; + + /* Cheat, the only const line we'll actually get is "" */ + line = (char *) const_line; + opt = strtok(line, " \t="); + if (!opt) + return 0; + + idx = index_in_strings(dhcp_option_strings, opt); /* NB: was strcasecmp! */ + if (idx < 0) + return 0; + option = &dhcp_options[idx]; + + retval = 0; + do { val = strtok(NULL, ", \t"); - if(!val) + if (!val) break; + length = dhcp_option_lengths[option->flags & TYPE_MASK]; + retval = 0; + opt = buffer; /* new meaning for variable opt */ + switch (option->flags & TYPE_MASK) { + case OPTION_IP: + retval = read_ip(val, buffer); break; - length = option_lengths[option->flags & TYPE_MASK]; - valptr = NULL; - switch (option->flags & TYPE_MASK) { - case OPTION_IP: - retval = read_ip(val, buffer); - break; - case OPTION_IP_PAIR: - retval = read_ip(val, buffer); - if (!(val = strtok(NULL, ", \t/-"))) retval = 0; - if (retval) retval = read_ip(val, buffer + 4); - break; - case OPTION_STRING: - length = strlen(val); - if (length > 0) { - if (length > 254) length = 254; - endptr = buffer + length; - endptr[0] = 0; - valptr = val; - } - break; - case OPTION_BOOLEAN: - retval = read_yn(val, buffer); - break; - case OPTION_U8: - buffer[0] = strtoul(val, &endptr, 0); - valptr = buffer; - break; - case OPTION_U16: - result_u16 = htons(strtoul(val, &endptr, 0)); - valptr = &result_u16; - break; - case OPTION_S16: - result_u16 = htons(strtol(val, &endptr, 0)); - valptr = &result_u16; - break; - case OPTION_U32: - result_u32 = htonl(strtoul(val, &endptr, 0)); - valptr = &result_u32; - break; - case OPTION_S32: - result_u32 = htonl(strtol(val, &endptr, 0)); - valptr = &result_u32; - break; - default: - retval = 0; - break; + case OPTION_IP_PAIR: + retval = read_ip(val, buffer); + val = strtok(NULL, ", \t/-"); + if (!val) + retval = 0; + if (retval) + retval = read_ip(val, buffer + 4); + break; + case OPTION_STRING: +#if ENABLE_FEATURE_UDHCP_RFC3397 + case OPTION_STR1035: +#endif + length = strlen(val); + if (length > 0) { + if (length > 254) length = 254; + opt = val; + retval = 1; } - if(valptr) { - memcpy(buffer, valptr, length); + break; + case OPTION_BOOLEAN: + retval = read_yn(val, buffer); + break; + case OPTION_U8: + buffer[0] = strtoul(val, &endptr, 0); + retval = (endptr[0] == '\0'); + break; + /* htonX are macros in older libc's, using temp var + * in code below for safety */ + /* TODO: use bb_strtoX? */ + case OPTION_U16: { + unsigned long tmp = strtoul(val, &endptr, 0); + *result_u16 = htons(tmp); + retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/); + break; + } + case OPTION_S16: { + long tmp = strtol(val, &endptr, 0); + *result_u16 = htons(tmp); + retval = (endptr[0] == '\0'); + break; + } + case OPTION_U32: { + unsigned long tmp = strtoul(val, &endptr, 0); + *result_u32 = htonl(tmp); retval = (endptr[0] == '\0'); + break; } - if (retval) - attach_option(opt_list, option, buffer, length); - else + case OPTION_S32: { + long tmp = strtol(val, &endptr, 0); + *result_u32 = htonl(tmp); + retval = (endptr[0] == '\0'); break; - } while (option->flags & OPTION_LIST); - } + } + default: + break; + } + if (retval) + attach_option(opt_list, option, opt, length); + } while (retval && option->flags & OPTION_LIST); return retval; } +static int read_staticlease(const char *const_line, void *arg) +{ + char *line; + char *mac_string; + char *ip_string; + struct ether_addr mac_bytes; + uint32_t ip; -static const struct config_keyword keywords[] = { - /* keyword handler variable address default */ - {"start", read_ip, &(server_config.start), "192.168.0.20"}, - {"end", read_ip, &(server_config.end), "192.168.0.254"}, - {"interface", read_str, &(server_config.interface), "eth0"}, - {"option", read_opt, &(server_config.options), ""}, - {"opt", read_opt, &(server_config.options), ""}, - {"max_leases", read_u32, &(server_config.max_leases), "254"}, - {"remaining", read_yn, &(server_config.remaining), "yes"}, - {"auto_time", read_u32, &(server_config.auto_time), "7200"}, - {"decline_time",read_u32, &(server_config.decline_time),"3600"}, - {"conflict_time",read_u32,&(server_config.conflict_time),"3600"}, - {"offer_time", read_u32, &(server_config.offer_time), "60"}, - {"min_lease", read_u32, &(server_config.min_lease), "60"}, - {"lease_file", read_str, &(server_config.lease_file), leases_file}, - {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"}, - {"notify_file", read_str, &(server_config.notify_file), ""}, - {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"}, - {"sname", read_str, &(server_config.sname), ""}, - {"boot_file", read_str, &(server_config.boot_file), ""}, - /*ADDME: static lease */ - {"", NULL, NULL, ""} + /* Read mac */ + line = (char *) const_line; + mac_string = strtok_r(line, " \t", &line); + read_mac(mac_string, &mac_bytes); + + /* Read ip */ + ip_string = strtok_r(NULL, " \t", &line); + read_ip(ip_string, &ip); + + addStaticLease(arg, (uint8_t*) &mac_bytes, ip); + + if (ENABLE_UDHCP_DEBUG) printStaticLeases(arg); + + return 1; +} + + +struct config_keyword { + const char *keyword; + int (*handler)(const char *line, void *var); + void *var; + const char *def; }; +static const struct config_keyword keywords[] = { + /* keyword handler variable address default */ + {"start", read_ip, &(server_config.start_ip), "192.168.0.20"}, + {"end", read_ip, &(server_config.end_ip), "192.168.0.254"}, + {"interface", read_str, &(server_config.interface), "eth0"}, + /* Avoid "max_leases value not sane" warning by setting default + * to default_end_ip - default_start_ip + 1: */ + {"max_leases", read_u32, &(server_config.max_leases), "235"}, +// {"remaining", read_yn, &(server_config.remaining), "yes"}, + {"auto_time", read_u32, &(server_config.auto_time), "7200"}, + {"decline_time", read_u32, &(server_config.decline_time), "3600"}, + {"conflict_time",read_u32, &(server_config.conflict_time),"3600"}, + {"offer_time", read_u32, &(server_config.offer_time), "60"}, + {"min_lease", read_u32, &(server_config.min_lease), "60"}, + {"lease_file", read_str, &(server_config.lease_file), LEASES_FILE}, + {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"}, + {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"}, + /* keywords with no defaults must be last! */ + {"option", read_opt, &(server_config.options), ""}, + {"opt", read_opt, &(server_config.options), ""}, + {"notify_file", read_str, &(server_config.notify_file), ""}, + {"sname", read_str, &(server_config.sname), ""}, + {"boot_file", read_str, &(server_config.boot_file), ""}, + {"static_lease", read_staticlease, &(server_config.static_leases), ""}, +}; +enum { KWS_WITH_DEFAULTS = ARRAY_SIZE(keywords) - 6 }; -int read_config(const char *file) +void FAST_FUNC read_config(const char *file) { - FILE *in; - char buffer[READ_CONFIG_BUF_SIZE], orig[READ_CONFIG_BUF_SIZE]; - char *token, *line; - int i; + parser_t *parser; + const struct config_keyword *k; + unsigned i; + char *token[2]; - for (i = 0; keywords[i].keyword[0]; i++) - if (keywords[i].def[0]) - keywords[i].handler(keywords[i].def, keywords[i].var); + for (i = 0; i < KWS_WITH_DEFAULTS; i++) + keywords[i].handler(keywords[i].def, keywords[i].var); - if (!(in = fopen(file, "r"))) { - LOG(LOG_ERR, "unable to open config file: %s", file); - return 0; - } - - while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) { - if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0'; - strcpy(orig, buffer); - if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0'; - token = strtok(buffer, " \t"); - if(!token) - continue; - line = strtok(NULL, ""); - if(!line) - continue; - while(*line == '=' || isspace(*line)) - line++; - /* eat trailing whitespace */ - for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--); - line[i] = '\0'; - if (*line == '\0') - continue; - - for (i = 0; keywords[i].keyword[0]; i++) - if (!strcasecmp(token, keywords[i].keyword)) - if (!keywords[i].handler(line, keywords[i].var)) { - LOG(LOG_ERR, "unable to parse '%s'", orig); + parser = config_open(file); + while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL)) { + for (k = keywords, i = 0; i < ARRAY_SIZE(keywords); k++, i++) { + if (!strcasecmp(token[0], k->keyword)) { + if (!k->handler(token[1], k->var)) { + bb_error_msg("can't parse line %u in %s", + parser->lineno, file); /* reset back to the default value */ - keywords[i].handler(keywords[i].def, keywords[i].var); + k->handler(k->def, k->var); } + break; + } + } } - fclose(in); - return 1; + config_close(parser); + + server_config.start_ip = ntohl(server_config.start_ip); + server_config.end_ip = ntohl(server_config.end_ip); } -void write_leases(void) +void FAST_FUNC write_leases(void) { - FILE *fp; - unsigned int i; - char buf[255]; - time_t curr = time(0); - unsigned long lease_time; - - if (!(fp = fopen(server_config.lease_file, "w"))) { - LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file); + int fd; + unsigned i; + leasetime_t curr; + int64_t written_at; + + fd = open_or_warn(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC); + if (fd < 0) return; - } - + + curr = written_at = time(NULL); + + written_at = hton64(written_at); + full_write(fd, &written_at, sizeof(written_at)); + for (i = 0; i < server_config.max_leases; i++) { - struct dhcpOfferedAddr lease; - if (leases[i].yiaddr != 0) { - if (server_config.remaining) { - if (lease_expired(&(leases[i]))) - lease_time = 0; - else lease_time = leases[i].expires - curr; - } else lease_time = leases[i].expires; - lease.expires = htonl(lease_time); - memcpy(lease.chaddr, leases[i].chaddr, 16); - lease.yiaddr = leases[i].yiaddr; - fwrite(leases, sizeof(lease), 1, fp); - } + leasetime_t tmp_time; + + if (leases[i].yiaddr == 0) + continue; + + /* Screw with the time in the struct, for easier writing */ + tmp_time = leases[i].expires; + + leases[i].expires -= curr; + if ((signed_leasetime_t) leases[i].expires < 0) + leases[i].expires = 0; + leases[i].expires = htonl(leases[i].expires); + + /* No error check. If the file gets truncated, + * we lose some leases on restart. Oh well. */ + full_write(fd, &leases[i], sizeof(leases[i])); + + /* Then restore it when done */ + leases[i].expires = tmp_time; } - fclose(fp); - + close(fd); + if (server_config.notify_file) { - sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file); - system(buf); +// TODO: vfork-based child creation + char *cmd = xasprintf("%s %s", server_config.notify_file, server_config.lease_file); + system(cmd); + free(cmd); } } -void read_leases(const char *file) +void FAST_FUNC read_leases(const char *file) { - FILE *fp; - unsigned int i = 0; struct dhcpOfferedAddr lease; - - if (!(fp = fopen(file, "r"))) { - LOG(LOG_ERR, "Unable to open %s for reading", file); + int64_t written_at, time_passed; + int fd; + USE_UDHCP_DEBUG(unsigned i;) + + fd = open_or_warn(file, O_RDONLY); + if (fd < 0) return; - } - - while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) { - /* ADDME: is it a static lease */ - if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) { - lease.expires = ntohl(lease.expires); - if (!server_config.remaining) lease.expires -= time(0); - if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) { - LOG(LOG_WARNING, "Too many leases while loading %s\n", file); + + if (full_read(fd, &written_at, sizeof(written_at)) != sizeof(written_at)) + goto ret; + written_at = ntoh64(written_at); + + time_passed = time(NULL) - written_at; + /* Strange written_at, or lease file from old version of udhcpd + * which had no "written_at" field? */ + if ((uint64_t)time_passed > 12 * 60 * 60) + goto ret; + + USE_UDHCP_DEBUG(i = 0;) + while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) { + /* ADDME: what if it matches some static lease? */ + uint32_t y = ntohl(lease.yiaddr); + if (y >= server_config.start_ip && y <= server_config.end_ip) { + signed_leasetime_t expires = ntohl(lease.expires) - (signed_leasetime_t)time_passed; + if (expires <= 0) + continue; + /* NB: add_lease takes "relative time", IOW, + * lease duration, not lease deadline. */ + if (!(add_lease(lease.chaddr, lease.yiaddr, expires, NULL /* was lease.hostname. bug in add_lease, disabled */ ))) { + bb_error_msg("too many leases while loading %s", file); break; - } - i++; + } + USE_UDHCP_DEBUG(i++;) } } - DEBUG(LOG_INFO, "Read %d leases", i); - fclose(fp); + DEBUG("Read %d leases", i); + ret: + close(fd); } |