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bcd94e2750

Stefan Eissing
Stefan Eissing
2026-04-14
SUCCESS Duration: 245s

Subject

socks: use dns filter for resolving

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

lib/cf-dns.c +26 -15lib/cf-dns.h +2 -1lib/socks.c +46 -76
lib/cf-dns.c+26 -15
@@ -44,6 +44,7 @@ struct cf_dns_ctx {
BIT(started);
BIT(announced);
BIT(abstract_unix_socket);
+ BIT(complete_resolve);
char hostname[1];
};
@@ -52,6 +53,7 @@ static struct cf_dns_ctx *cf_dns_ctx_create(struct Curl_easy *data,
const char *hostname,
uint16_t port, uint8_t transport,
bool abstract_unix_socket,
+ bool complete_resolve,
struct Curl_dns_entry *dns)
{
struct cf_dns_ctx *ctx;
@@ -65,11 +67,14 @@ static struct cf_dns_ctx *cf_dns_ctx_create(struct Curl_easy *data,
ctx->dns_queries = dns_queries;
ctx->transport = transport;
ctx->abstract_unix_socket = abstract_unix_socket;
+ ctx->complete_resolve = complete_resolve;
ctx->dns = Curl_dns_entry_link(data, dns);
ctx->started = !!ctx->dns;
if(hlen)
memcpy(ctx->hostname, hostname, hlen);
+ CURL_TRC_DNS(data, "created DNS filter for %s:%u, transport=%x, queries=%x",
+ ctx->hostname, ctx->port, ctx->transport, ctx->dns_queries);
return ctx;
}
@@ -240,20 +245,23 @@ static CURLcode cf_dns_connect(struct Curl_cfilter *cf,
}
if(cf->next && !cf->next->connected) {
- CURLcode result = Curl_conn_cf_connect(cf->next, data, done);
- CURL_TRC_CF(data, cf, "connect subfilters -> %d, done=%d", result, *done);
- if(result || !*done)
+ bool sub_done;
+ CURLcode result = Curl_conn_cf_connect(cf->next, data, &sub_done);
+ CURL_TRC_CF(data, cf, "connect subfilters -> %d, done=%d",
+ result, sub_done);
+ if(result || !sub_done)
return result;
+ DEBUGASSERT(sub_done);
}
- /* sub filter chain is connected, so are we now.
- * Unlink the DNS entry, it is no longer needed and if it
- * came from a SHARE in `data`, we need to release it under
- * that one's lock. */
- DEBUGASSERT(*done);
+ /* sub filter chain is connected */
+ if(ctx->complete_resolve && !ctx->dns && !ctx->resolv_result) {
+ /* This filter only connects when it has resolved everything. */
+ return CURLE_OK;
+ }
+ *done = TRUE;
cf->connected = TRUE;
Curl_resolv_destroy(data, ctx->resolv_id);
- Curl_dns_entry_unlink(data, &ctx->dns);
return CURLE_OK;
}
@@ -336,6 +344,7 @@ static CURLcode cf_dns_create(struct Curl_cfilter **pcf,
uint16_t port,
uint8_t transport,
bool abstract_unix_socket,
+ bool complete_resolve,
struct Curl_dns_entry *dns)
{
struct Curl_cfilter *cf = NULL;
@@ -344,7 +353,7 @@ static CURLcode cf_dns_create(struct Curl_cfilter **pcf,
(void)data;
ctx = cf_dns_ctx_create(data, dns_queries, hostname, port, transport,
- abstract_unix_socket, dns);
+ abstract_unix_socket, complete_resolve, dns);
if(!ctx) {
result = CURLE_OUT_OF_MEMORY;
goto out;
@@ -365,6 +374,7 @@ static CURLcode cf_dns_conn_create(struct Curl_cfilter **pcf,
struct Curl_easy *data,
uint8_t dns_queries,
uint8_t transport,
+ bool complete_resolve,
struct Curl_dns_entry *dns)
{
struct connectdata *conn = data->conn;
@@ -409,7 +419,7 @@ static CURLcode cf_dns_conn_create(struct Curl_cfilter **pcf,
}
return cf_dns_create(pcf, data, dns_queries,
hostname, port, transport,
- abstract_unix_socket, dns);
+ abstract_unix_socket, complete_resolve, dns);
}
/* Adds a "resolv" filter at the top of the connection's filter chain.
@@ -430,11 +440,11 @@ CURLcode Curl_cf_dns_add(struct Curl_easy *data,
DEBUGASSERT(data);
if(sockindex == FIRSTSOCKET)
- result = cf_dns_conn_create(&cf, data, dns_queries, transport, dns);
+ result = cf_dns_conn_create(&cf, data, dns_queries, transport, FALSE, dns);
else if(dns) {
result = cf_dns_create(&cf, data, dns_queries,
dns->hostname, dns->port, transport,
- FALSE, dns);
+ FALSE, FALSE, dns);
}
else {
DEBUGASSERT(0);
@@ -458,14 +468,15 @@ CURLcode Curl_cf_dns_insert_after(struct Curl_cfilter *cf_at,
uint8_t dns_queries,
const char *hostname,
uint16_t port,
- uint8_t transport)
+ uint8_t transport,
+ bool complete_resolve)
{
struct Curl_cfilter *cf;
CURLcode result;
result = cf_dns_create(&cf, data, dns_queries,
hostname, port, transport,
- FALSE, NULL);
+ FALSE, complete_resolve, NULL);
if(result)
return result;
lib/cf-dns.h+2 -1
@@ -42,7 +42,8 @@ CURLcode Curl_cf_dns_insert_after(struct Curl_cfilter *cf_at,
uint8_t dns_queries,
const char *hostname,
uint16_t port,
- uint8_t transport);
+ uint8_t transport,
+ bool complete_resolve);
CURLcode Curl_conn_dns_result(struct connectdata *conn, int sockindex);
CURLcode Curl_cf_dns_result(struct Curl_cfilter *cf);
lib/socks.c+46 -76
@@ -38,6 +38,7 @@
#include "curl_trc.h"
#include "select.h"
#include "cfilters.h"
+#include "cf-dns.h"
#include "connect.h"
#include "socks.h"
#include "curlx/inet_pton.h"
@@ -313,71 +314,54 @@ static CURLproxycode socks4_resolving(struct socks_state *sx,
struct Curl_easy *data,
bool *done)
{
- struct Curl_dns_entry *dns = NULL;
- struct Curl_addrinfo *hp = NULL;
+ const struct Curl_addrinfo *ai = NULL;
CURLcode result;
size_t nwritten;
+ bool dns_done;
*done = FALSE;
if(sx->start_resolving) {
/* need to resolve hostname to add destination address */
sx->start_resolving = FALSE;
DEBUGASSERT(sx->hostname && *sx->hostname);
-
- result = Curl_resolv(data,
- Curl_resolv_dns_queries(data, cf->conn->ip_version),
- sx->hostname, sx->remote_port,
- Curl_conn_cf_get_transport(cf, data),
- 0, &sx->resolv_id, &dns);
- if(result == CURLE_AGAIN) {
- CURL_TRC_CF(data, cf, "SOCKS4 non-blocking resolve of %s", sx->hostname);
- return CURLPX_OK;
+ result = Curl_cf_dns_insert_after(
+ cf, data, Curl_resolv_dns_queries(data, cf->conn->ip_version),
+ sx->hostname, sx->remote_port, TRNSPRT_TCP, TRUE);
+ if(result) {
+ failf(data, "unable to create DNS filter for socks");
+ return CURLPX_UNKNOWN_FAIL;
}
- else if(result)
- return CURLPX_RESOLVE_HOST;
- }
- else {
- /* check if we have the name resolved by now */
- result = Curl_resolv_take_result(data, sx->resolv_id, &dns);
- if(!result && !dns)
- return CURLPX_OK;
}
- if(result || !dns) {
- failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.", sx->hostname);
- if(dns)
- Curl_dns_entry_unlink(data, &dns);
+ /* resolve the hostname by connecting the DNS filter */
+ result = Curl_conn_cf_connect(cf->next, data, &dns_done);
+ if(result) {
+ failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.",
+ sx->hostname);
return CURLPX_RESOLVE_HOST;
}
+ else if(!dns_done)
+ return CURLPX_OK;
- /*
- * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
- * returns a Curl_addrinfo pointer that may not always look the same.
- */
- /* scan for the first IPv4 address */
- hp = dns->addr;
- while(hp && (hp->ai_family != AF_INET))
- hp = hp->ai_next;
-
- if(hp) {
+ ai = Curl_cf_dns_get_ai(cf->next, data, AF_INET, 0);
+ if(ai) {
struct sockaddr_in *saddr_in;
char ipbuf[64];
- Curl_printable_address(hp, ipbuf, sizeof(ipbuf));
+ Curl_printable_address(ai, ipbuf, sizeof(ipbuf));
CURL_TRC_CF(data, cf, "SOCKS4 connect to IPv4 %s (locally resolved)",
ipbuf);
- saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
+ saddr_in = (struct sockaddr_in *)(void *)ai->ai_addr;
result = Curl_bufq_write(&sx->iobuf,
(unsigned char *)&saddr_in->sin_addr.s_addr, 4,
&nwritten);
- Curl_dns_entry_unlink(data, &dns); /* not used anymore from now on */
if(result || (nwritten != 4))
return CURLPX_SEND_REQUEST;
}
else {
- Curl_dns_entry_unlink(data, &dns);
+ /* No ipv4 address resolved */
failf(data, "SOCKS4 connection to %s not supported", sx->hostname);
return CURLPX_RESOLVE_HOST;
}
@@ -844,8 +828,7 @@ static CURLproxycode socks5_resolving(struct socks_state *sx,
struct Curl_easy *data,
bool *done)
{
- struct Curl_dns_entry *dns = NULL;
- struct Curl_addrinfo *hp = NULL;
+ const struct Curl_addrinfo *ai = NULL;
char dest[MAX_IPADR_LEN]; /* printable address */
const unsigned char *destination = NULL;
unsigned char desttype = 1, destlen = 4;
@@ -853,72 +836,61 @@ static CURLproxycode socks5_resolving(struct socks_state *sx,
CURLcode result;
CURLproxycode presult = CURLPX_OK;
size_t nwritten;
+ bool dns_done;
*done = FALSE;
if(sx->start_resolving) {
/* need to resolve hostname to add destination address */
sx->start_resolving = FALSE;
DEBUGASSERT(sx->hostname && *sx->hostname);
-
- result = Curl_resolv(data,
- Curl_resolv_dns_queries(data, cf->conn->ip_version),
- sx->hostname, sx->remote_port,
- Curl_conn_cf_get_transport(cf, data),
- 0, &sx->resolv_id, &dns);
- if(result == CURLE_AGAIN) {
- CURL_TRC_CF(data, cf, "SOCKS5 non-blocking resolve of %s", sx->hostname);
- return CURLPX_OK;
+ result = Curl_cf_dns_insert_after(
+ cf, data, Curl_resolv_dns_queries(data, cf->conn->ip_version),
+ sx->hostname, sx->remote_port, TRNSPRT_TCP, TRUE);
+ if(result) {
+ failf(data, "unable to create DNS filter for socks");
+ return CURLPX_UNKNOWN_FAIL;
}
- else if(result)
- return CURLPX_RESOLVE_HOST;
- }
- else {
- /* check if we have the name resolved by now */
- result = Curl_resolv_take_result(data, sx->resolv_id, &dns);
- if(!result && !dns)
- return CURLPX_OK;
}
- if(result || !dns) {
+ /* resolve the hostname by connecting the DNS filter */
+ result = Curl_conn_cf_connect(cf->next, data, &dns_done);
+ if(result) {
failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.", sx->hostname);
- presult = CURLPX_RESOLVE_HOST;
- goto out;
+ return CURLPX_RESOLVE_HOST;
}
+ else if(!dns_done)
+ return CURLPX_OK;
- if(dns)
- hp = dns->addr;
#ifdef USE_IPV6
- if(data->set.ipver != CURL_IPRESOLVE_WHATEVER) {
- int wanted_family = data->set.ipver == CURL_IPRESOLVE_V4 ?
- AF_INET : AF_INET6;
- /* scan for the first proper address */
- while(hp && (hp->ai_family != wanted_family))
- hp = hp->ai_next;
- }
+ if(data->set.ipver != CURL_IPRESOLVE_V4)
+ ai = Curl_cf_dns_get_ai(cf->next, data, AF_INET6, 0);
#endif
- if(!hp) {
+ if(!ai)
+ ai = Curl_cf_dns_get_ai(cf->next, data, AF_INET, 0);
+
+ if(!ai) {
failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.", sx->hostname);
presult = CURLPX_RESOLVE_HOST;
goto out;
}
- Curl_printable_address(hp, dest, sizeof(dest));
+ Curl_printable_address(ai, dest, sizeof(dest));
- if(hp->ai_family == AF_INET) {
+ if(ai->ai_family == AF_INET) {
struct sockaddr_in *saddr_in;
desttype = 1; /* ATYP: IPv4 = 1 */
destlen = 4;
- saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
+ saddr_in = (struct sockaddr_in *)(void *)ai->ai_addr;
destination = (const unsigned char *)&saddr_in->sin_addr.s_addr;
CURL_TRC_CF(data, cf, "SOCKS5 connect to %s:%u (locally resolved)",
dest, sx->remote_port);
}
#ifdef USE_IPV6
- else if(hp->ai_family == AF_INET6) {
+ else if(ai->ai_family == AF_INET6) {
struct sockaddr_in6 *saddr_in6;
desttype = 4; /* ATYP: IPv6 = 4 */
destlen = 16;
- saddr_in6 = (struct sockaddr_in6 *)(void *)hp->ai_addr;
+ saddr_in6 = (struct sockaddr_in6 *)(void *)ai->ai_addr;
destination = (const unsigned char *)&saddr_in6->sin6_addr.s6_addr;
CURL_TRC_CF(data, cf, "SOCKS5 connect to [%s]:%u (locally resolved)",
dest, sx->remote_port);
@@ -952,8 +924,6 @@ static CURLproxycode socks5_resolving(struct socks_state *sx,
}
out:
- if(dns)
- Curl_dns_entry_unlink(data, &dns);
*done = (presult == CURLPX_OK);
return presult;
}