diff options
| -rw-r--r-- | evdns.c | 88 | ||||
| -rw-r--r-- | evdns.h | 2 |
2 files changed, 65 insertions, 25 deletions
@@ -1898,6 +1898,64 @@ strtoint(const char *const str) { return r; } +// helper version of atoi that returns -1 on error and clips to bounds. +static int +strtoint_clipped(const char *const str, int min, int max) +{ + int r = strtoint(str); + if (r == -1) + return r; + else if (r<min) + return min; + else if (r>max) + return max; + else + return r; +} + +// exported function +int +evdns_set_option(const char *option, const char *val, int flags) +{ + if (!strncmp(option, "ndots:", 6)) { + const int ndots = strtoint(val); + if (ndots == -1) return -1; + if (!(flags & DNS_OPTION_SEARCH)) return 0; + log(EVDNS_LOG_DEBUG, "Setting ndots to %d", ndots); + if (!global_search_state) global_search_state = search_state_new(); + if (!global_search_state) return -1; + global_search_state->ndots = ndots; + } else if (!strncmp(option, "timeout:", 8)) { + const int timeout = strtoint(val); + if (timeout == -1) return -1; + if (!(flags & DNS_OPTION_MISC)) return 0; + log(EVDNS_LOG_DEBUG, "Setting timeout to %d", timeout); + global_timeout.tv_sec = timeout; + } else if (!strncmp(option, "max-timeouts:", 12)) { + const int maxtimeout = strtoint_clipped(val, 1, 255); + if (maxtimeout == -1) return -1; + if (!(flags & DNS_OPTION_MISC)) return 0; + log(EVDNS_LOG_DEBUG, "Setting maximum allowed timeouts to %d", + maxtimeout); + global_max_nameserver_timeout = maxtimeout; + } else if (!strncmp(option, "max-inflight:", 13)) { + const int maxinflight = strtoint_clipped(val, 1, 65000); + if (maxinflight == -1) return -1; + if (!(flags & DNS_OPTION_MISC)) return 0; + log(EVDNS_LOG_DEBUG, "Setting maximum inflight requests to %d", + maxinflight); + global_max_requests_inflight = maxinflight; + } else if (!strncmp(option, "attempts:", 9)) { + int retries = strtoint(val); + if (retries == -1) return -1; + if (retries > 255) retries = 255; + if (!(flags & DNS_OPTION_MISC)) return 0; + log(EVDNS_LOG_DEBUG, "Setting retries to %d", retries); + global_max_retransmits = retries; + } + return 0; +} + static void resolv_conf_parse_line(char *const start, int flags) { char *strtok_state; @@ -1907,7 +1965,7 @@ resolv_conf_parse_line(char *const start, int flags) { char *const first_token = strtok_r(start, delims, &strtok_state); if (!first_token) return; - if (!strcmp(first_token, "nameserver")) { + if (!strcmp(first_token, "nameserver") && (flags & DNS_OPTION_NAMESERVERS)) { const char *const nameserver = NEXT_TOKEN; struct in_addr ina; @@ -1931,30 +1989,9 @@ resolv_conf_parse_line(char *const start, int flags) { search_reverse(); } else if (!strcmp(first_token, "options")) { const char *option; - while ((option = NEXT_TOKEN)) { - if (!strncmp(option, "ndots:", 6)) { - const int ndots = strtoint(&option[6]); - if (ndots == -1) continue; - if (!(flags & DNS_OPTION_SEARCH)) continue; - log(EVDNS_LOG_DEBUG, "Setting ndots to %d", ndots); - if (!global_search_state) global_search_state = search_state_new(); - if (!global_search_state) return; - global_search_state->ndots = ndots; - } else if (!strncmp(option, "timeout:", 8)) { - const int timeout = strtoint(&option[8]); - if (timeout == -1) continue; - if (!(flags & DNS_OPTION_MISC)) continue; - log(EVDNS_LOG_DEBUG, "Setting timeout to %d", timeout); - global_timeout.tv_sec = timeout; - } else if (!strncmp(option, "attempts:", 9)) { - int retries = strtoint(&option[9]); - if (retries == -1) continue; - if (retries > 255) retries = 255; - if (!(flags & DNS_OPTION_MISC)) continue; - log(EVDNS_LOG_DEBUG, "Setting retries to %d", retries); - global_max_retransmits = retries; - } + const char *val = strchr(option, ':'); + evdns_set_option(option, val ? val+1 : "", flags); } } #undef NEXT_TOKEN @@ -1987,7 +2024,7 @@ evdns_resolv_conf_parse(int flags, const char *const filename) { if (fstat(fd, &st)) { err = 2; goto out1; } if (!st.st_size) { evdns_resolv_set_defaults(flags); - err = 0; + err = (flags & DNS_OPTION_NAMESERVERS) ? 6 : 0; goto out1; } if (st.st_size > 65535) { err = 3; goto out1; } // no resolv.conf should be any bigger @@ -2016,6 +2053,7 @@ evdns_resolv_conf_parse(int flags, const char *const filename) { if (!server_head && (flags & DNS_OPTION_NAMESERVERS)) { // no nameservers were configured. evdns_nameserver_ip_add("127.0.0.1"); + err = 6; } if (flags & DNS_OPTION_SEARCH && (!global_search_state || global_search_state->num_domains == 0)) { search_set_from_hostname(); @@ -213,6 +213,7 @@ * 3 file too large * 4 out of memory * 5 short read from file + * 6 no nameservers in file * * Internals: * @@ -298,6 +299,7 @@ struct in_addr; struct in6_addr; int evdns_resolve_reverse(struct in_addr *in, int flags, evdns_callback_type callback, void *ptr); int evdns_resolve_reverse_ipv6(struct in6_addr *in, int flags, evdns_callback_type callback, void *ptr); +int evdns_set_option(const char *option, const char *val, int flags); int evdns_resolv_conf_parse(int flags, const char *); #ifdef MS_WINDOWS int evdns_config_windows_nameservers(void); |