From 50d1b3379a818df00c6382d68e2e39977cc96cd6 Mon Sep 17 00:00:00 2001 From: Anders Bakken Date: Tue, 30 Jan 2018 16:33:51 -0800 Subject: CURLOPT_RESOLVE: Add support for multiple IP addresses per entry This enables users to preresolve but still take advantage of happy eyeballs and trying multiple addresses if some are not connecting. Ref: https://github.com/curl/curl/pull/2260 --- lib/hostip.c | 116 +++++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 89 insertions(+), 27 deletions(-) (limited to 'lib/hostip.c') diff --git a/lib/hostip.c b/lib/hostip.c index 886aeec42..8310c83e1 100644 --- a/lib/hostip.c +++ b/lib/hostip.c @@ -781,7 +781,7 @@ CURLcode Curl_loadhostpairs(struct Curl_easy *data) { struct curl_slist *hostp; char hostname[256]; - int port; + int port = 0; for(hostp = data->change.resolve; hostp; hostp = hostp->next) { if(!hostp->data) @@ -819,32 +819,95 @@ CURLcode Curl_loadhostpairs(struct Curl_easy *data) } else { struct Curl_dns_entry *dns; - Curl_addrinfo *addr; + Curl_addrinfo *head = NULL, *tail = NULL; char *entry_id; size_t entry_len; - char buffer[256]; - char *address = &buffer[0]; + char address[64]; + char *addresses; + char *addr_begin; + char *addr_end; + char *port_ptr; + char *end_ptr; + char *host_end; + unsigned long tmp_port; + bool error = true; + + host_end = strchr(hostp->data, ':'); + if(!host_end || + ((host_end - hostp->data) >= (ptrdiff_t)sizeof(hostname))) + goto err; + + memcpy(hostname, hostp->data, host_end - hostp->data); + hostname[host_end - hostp->data] = '\0'; + + port_ptr = host_end + 1; + tmp_port = strtoul(port_ptr, &end_ptr, 10); + if(end_ptr == port_ptr || tmp_port > USHRT_MAX || *end_ptr != ':') + goto err; + + port = (int)tmp_port; + addresses = end_ptr + 1; + + while(*end_ptr) { + size_t alen; + Curl_addrinfo *ai; + + addr_begin = end_ptr + 1; + addr_end = strchr(addr_begin, ','); + if(!addr_end) + addr_end = addr_begin + strlen(addr_begin); + end_ptr = addr_end; + + /* allow IP(v6) address within [brackets] */ + if(*addr_begin == '[') { + if(addr_end == addr_begin || *(addr_end - 1) != ']') + goto err; + ++addr_begin; + --addr_end; + } - if(3 != sscanf(hostp->data, "%255[^:]:%d:%255s", hostname, &port, - address)) { - infof(data, "Couldn't parse CURLOPT_RESOLVE entry '%s'!\n", - hostp->data); - continue; - } + alen = addr_end - addr_begin; + if(!alen) + continue; - /* allow IP(v6) address within [brackets] */ - if(address[0] == '[') { - size_t alen = strlen(address); - if(address[alen-1] != ']') - /* it needs to also end with ] to be valid */ + if(alen >= sizeof(address)) + goto err; + + memcpy(address, addr_begin, alen); + address[alen] = '\0'; + +#ifndef ENABLE_IPV6 + if(strchr(address, ':')) { + infof(data, "Ignoring resolve address '%s', missing IPv6 support.\n", + address); continue; - address[alen-1] = 0; /* zero terminate there */ - address++; /* pass the open bracket */ + } +#endif + + ai = Curl_str2addr(address, port); + if(!ai) { + infof(data, "Resolve address '%s' found illegal!\n", address); + goto err; + } + + if(tail) { + tail->ai_next = ai; + tail = tail->ai_next; + } + else { + head = tail = ai; + } } - addr = Curl_str2addr(address, port); - if(!addr) { - infof(data, "Address in '%s' found illegal!\n", hostp->data); + if(!head) + goto err; + + error = false; + err: + if(error) { + infof(data, "Couldn't parse CURLOPT_RESOLVE entry '%s'!\n", + hostp->data); + Curl_freeaddrinfo(head); continue; } @@ -852,10 +915,9 @@ CURLcode Curl_loadhostpairs(struct Curl_easy *data) entry_id = create_hostcache_id(hostname, port); /* If we can't create the entry id, fail */ if(!entry_id) { - Curl_freeaddrinfo(addr); + Curl_freeaddrinfo(head); return CURLE_OUT_OF_MEMORY; } - entry_len = strlen(entry_id); if(data->share) @@ -869,7 +931,7 @@ CURLcode Curl_loadhostpairs(struct Curl_easy *data) if(!dns) { /* if not in the cache already, put this host in the cache */ - dns = Curl_cache_addr(data, addr, hostname, port); + dns = Curl_cache_addr(data, head, hostname, port); if(dns) { dns->timestamp = 0; /* mark as added by CURLOPT_RESOLVE */ /* release the returned reference; the cache itself will keep the @@ -880,19 +942,19 @@ CURLcode Curl_loadhostpairs(struct Curl_easy *data) else { /* this is a duplicate, free it again */ infof(data, "RESOLVE %s:%d is already cached, %s not stored!\n", - hostname, port, address); - Curl_freeaddrinfo(addr); + hostname, port, addresses); + Curl_freeaddrinfo(head); } if(data->share) Curl_share_unlock(data, CURL_LOCK_DATA_DNS); if(!dns) { - Curl_freeaddrinfo(addr); + Curl_freeaddrinfo(head); return CURLE_OUT_OF_MEMORY; } infof(data, "Added %s:%d:%s to DNS cache\n", - hostname, port, address); + hostname, port, addresses); } } data->change.resolve = NULL; /* dealt with now */ -- cgit v1.2.3