curlx_inet_ntop: return CURLcode, drop setting errno

To simplify and to remove an exception where `errno` was reused to
return a socket error codes on Windows.

The error was used by one call site (`sockaddr2string()` in
`cf-socket.c`), but it was in practice always propagated as
`SOCKEAFNOSUPPORT` to callers.

Also:
- cf-socket: update 3 error messages to show `CURLcode` accordingly.
- if2ip: handle `curlx_inet_ntop()` error in `Curl_if2ip()`.
- dnsd: display `CURLcode` on two errors.

Follow-up to 39dec13ec0 #22170

Closes #22229
This commit is contained in:
Viktor Szakats 2026-06-30 18:10:23 +02:00
parent c2da5c7e66
commit bb406386d9
No known key found for this signature in database
11 changed files with 81 additions and 110 deletions

View file

@ -86,14 +86,15 @@
#endif
/* retrieves ip address and port from a sockaddr structure. note it calls
* curlx_inet_ntop which sets errno on fail, not SOCKERRNO.
* curlx_inet_ntop() and returns CURLcode.
* @unittest 1607
*/
UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
char *addr, uint16_t *port);
UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
char *addr, uint16_t *port)
UNITTEST CURLcode sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
char *addr, uint16_t *port);
UNITTEST CURLcode sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
char *addr, uint16_t *port)
{
CURLcode result;
struct sockaddr_in *si = NULL;
#ifdef USE_IPV6
struct sockaddr_in6 *si6 = NULL;
@ -107,17 +108,21 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
switch(sa->sa_family) {
case AF_INET:
si = (struct sockaddr_in *)(void *)sa;
if(curlx_inet_ntop(sa->sa_family, &si->sin_addr, addr, MAX_IPADR_LEN)) {
result = curlx_inet_ntop(sa->sa_family, &si->sin_addr, addr,
MAX_IPADR_LEN);
if(!result) {
*port = ntohs(si->sin_port);
return TRUE;
return result;
}
break;
#ifdef USE_IPV6
case AF_INET6:
si6 = (struct sockaddr_in6 *)(void *)sa;
if(curlx_inet_ntop(sa->sa_family, &si6->sin6_addr, addr, MAX_IPADR_LEN)) {
result = curlx_inet_ntop(sa->sa_family, &si6->sin6_addr, addr,
MAX_IPADR_LEN);
if(!result) {
*port = ntohs(si6->sin6_port);
return TRUE;
return result;
}
break;
#endif
@ -130,16 +135,16 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
else
addr[0] = 0; /* socket with no name */
*port = 0;
return TRUE;
return CURLE_OK;
#endif
default:
result = CURLE_UNSUPPORTED_PROTOCOL;
break;
}
addr[0] = '\0';
*port = 0;
errno = SOCKEAFNOSUPPORT;
return FALSE;
return result;
}
static void tcpnodelay(struct Curl_cfilter *cf,
@ -1087,18 +1092,19 @@ static void set_local_ip(struct Curl_cfilter *cf,
/* TFTP does not connect, so it cannot get the IP like this */
struct Curl_sockaddr_storage ssloc;
curl_socklen_t slen = sizeof(struct Curl_sockaddr_storage);
VERBOSE(char buffer[STRERROR_LEN]);
memset(&ssloc, 0, sizeof(ssloc));
if(getsockname(ctx->sock, (struct sockaddr *)&ssloc, &slen)) {
VERBOSE(char buffer[STRERROR_LEN]);
VERBOSE(int sockerr = SOCKERRNO);
infof(data, "getsockname() failed with errno %d: %s",
sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
}
else if(!sockaddr2string((struct sockaddr *)&ssloc, slen,
ctx->ip.local_ip, &ctx->ip.local_port)) {
infof(data, "ssloc inet_ntop() failed with errno %d: %s",
errno, curlx_strerror(errno, buffer, sizeof(buffer)));
else {
CURLcode result = sockaddr2string((struct sockaddr *)&ssloc, slen,
ctx->ip.local_ip, &ctx->ip.local_port);
if(result)
infof(data, "ssloc inet_ntop() failed with %d", (int)result);
}
}
#else
@ -1110,21 +1116,17 @@ static CURLcode set_remote_ip(struct Curl_cfilter *cf,
struct Curl_easy *data)
{
struct cf_socket_ctx *ctx = cf->ctx;
CURLcode result;
/* store remote address and port used in this connection attempt */
ctx->ip.transport = ctx->transport;
if(!sockaddr2string(&ctx->addr.curl_sa_addr,
(curl_socklen_t)ctx->addr.addrlen,
ctx->ip.remote_ip, &ctx->ip.remote_port)) {
char buffer[STRERROR_LEN];
/* using bare errno instead of SOCKERRNO is safe here, because
sockaddr2string() calls curlx_inet_ntop(), and they both report failures
via errno (even on Windows builds). */
ctx->sockerr = errno;
result = sockaddr2string(&ctx->addr.curl_sa_addr,
(curl_socklen_t)ctx->addr.addrlen,
ctx->ip.remote_ip, &ctx->ip.remote_port);
if(result) {
ctx->sockerr = SOCKEAFNOSUPPORT;
/* malformed address or bug in inet_ntop, try next address */
failf(data, "curl_sa_addr inet_ntop() failed with errno %d: %s",
errno, curlx_strerror(errno, buffer, sizeof(buffer)));
failf(data, "curl_sa_addr inet_ntop() failed with %d", (int)result);
return CURLE_FAILED_INIT;
}
return CURLE_OK;
@ -2156,7 +2158,7 @@ static void cf_tcp_set_accepted_remote_ip(struct Curl_cfilter *cf,
{
struct cf_socket_ctx *ctx = cf->ctx;
#ifdef HAVE_GETPEERNAME
char buffer[STRERROR_LEN];
CURLcode result;
struct Curl_sockaddr_storage ssrem;
curl_socklen_t plen;
@ -2165,15 +2167,16 @@ static void cf_tcp_set_accepted_remote_ip(struct Curl_cfilter *cf,
plen = sizeof(ssrem);
memset(&ssrem, 0, plen);
if(getpeername(ctx->sock, (struct sockaddr *)&ssrem, &plen)) {
char buffer[STRERROR_LEN];
int sockerr = SOCKERRNO;
failf(data, "getpeername() failed with errno %d: %s",
sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
return;
}
if(!sockaddr2string((struct sockaddr *)&ssrem, plen,
ctx->ip.remote_ip, &ctx->ip.remote_port)) {
failf(data, "ssrem inet_ntop() failed with errno %d: %s",
errno, curlx_strerror(errno, buffer, sizeof(buffer)));
result = sockaddr2string((struct sockaddr *)&ssrem, plen,
ctx->ip.remote_ip, &ctx->ip.remote_port);
if(result) {
failf(data, "ssrem inet_ntop() failed with %d", (int)result);
return;
}
#else

View file

@ -48,12 +48,12 @@
/*
* Format an IPv4 address, more or less like inet_ntop().
*
* Returns `dst' (as a const)
* Returns CURLcode.
* Note:
* - uses no static variables
* - takes an unsigned char* not an in_addr as input
*/
static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
static CURLcode inet_ntop4(const unsigned char *src, char *dst, size_t size)
{
char tmp[sizeof("255.255.255.255")];
size_t len;
@ -68,22 +68,16 @@ static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
((int)((unsigned char)src[3])) & 0xff);
len = strlen(tmp);
if(len == 0 || len >= size) {
#ifdef USE_WINSOCK
errno = WSAEINVAL;
#else
errno = ENOSPC;
#endif
return NULL;
}
if(len == 0 || len >= size)
return CURLE_TOO_LARGE;
curlx_strcopy(dst, size, tmp, len);
return dst;
return CURLE_OK;
}
/*
* Convert IPv6 binary address into presentation (printable) format.
*/
static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
static CURLcode inet_ntop6(const unsigned char *src, char *dst, size_t size)
{
/*
* Note that int32_t and int16_t need only be "at least" large enough
@ -152,9 +146,9 @@ static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
*/
if(i == 6 && best.base == 0 &&
(best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
if(!inet_ntop4(src + 12, tp, sizeof(tmp) - (tp - tmp))) {
return NULL;
}
CURLcode result = inet_ntop4(src + 12, tp, sizeof(tmp) - (tp - tmp));
if(result)
return result;
tp += strlen(tp);
break;
}
@ -181,31 +175,18 @@ static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
*tp++ = ':';
/* Check for overflow, copy, and we are done. */
if((size_t)(tp - tmp) >= size) {
#ifdef USE_WINSOCK
errno = WSAEINVAL;
#else
errno = ENOSPC;
#endif
return NULL;
}
if((size_t)(tp - tmp) >= size)
return CURLE_TOO_LARGE;
curlx_strcopy(dst, size, tmp, tp - tmp);
return dst;
return CURLE_OK;
}
/*
* Convert a network format address to presentation format.
*
* Returns pointer to presentation format address (`buf').
* Returns NULL on error and errno set with the specific
* error, EAFNOSUPPORT or ENOSPC.
*
* On Windows we store the error in the thread errno, not in the Winsock error
* code. This is to avoid losing the actual last Winsock error. When this
* function returns NULL, check errno not SOCKERRNO.
* Copies result to 'buf' and returns CURLcode.
*/
char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size)
CURLcode curlx_inet_ntop(int af, const void *src, char *buf, size_t size)
{
switch(af) {
case AF_INET:
@ -213,7 +194,6 @@ char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size)
case AF_INET6:
return inet_ntop6((const unsigned char *)src, buf, size);
default:
errno = SOCKEAFNOSUPPORT;
return NULL;
return CURLE_UNSUPPORTED_PROTOCOL;
}
}

View file

@ -25,6 +25,6 @@
***************************************************************************/
#include "curl_setup.h"
char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size);
CURLcode curlx_inet_ntop(int af, const void *src, char *buf, size_t size);
#endif /* HEADER_CURL_INET_NTOP_H */

View file

@ -1022,7 +1022,7 @@ static CURLcode ftp_port_default_host(struct Curl_easy *data,
struct sockaddr_in6 * const sa6 = (void *)sa;
#endif
char buffer[STRERROR_LEN];
const char *r;
CURLcode result;
*sslenp = sizeof(*ss);
if(getsockname(conn->sock[FIRSTSOCKET], sa, sslenp)) {
@ -1033,14 +1033,14 @@ static CURLcode ftp_port_default_host(struct Curl_easy *data,
switch(sa->sa_family) {
#ifdef USE_IPV6
case AF_INET6:
r = curlx_inet_ntop(sa->sa_family, &sa6->sin6_addr, hbuf, hbuflen);
result = curlx_inet_ntop(sa->sa_family, &sa6->sin6_addr, hbuf, hbuflen);
break;
#endif
default:
r = curlx_inet_ntop(sa->sa_family, &sa4->sin_addr, hbuf, hbuflen);
result = curlx_inet_ntop(sa->sa_family, &sa4->sin_addr, hbuf, hbuflen);
break;
}
if(!r)
if(result)
return CURLE_FTP_PORT_FAILED;
*hostp = hbuf;

View file

@ -112,9 +112,9 @@ if2ip_result_t Curl_if2ip(int af,
if(iface->ifa_addr->sa_family == af) {
if(curl_strequal(iface->ifa_name, interf)) {
void *addr;
const char *ip;
char scope[12] = "";
char ipstr[64];
CURLcode result;
#ifdef USE_IPV6
if(af == AF_INET6) {
#ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
@ -155,8 +155,8 @@ if2ip_result_t Curl_if2ip(int af,
addr =
&((struct sockaddr_in *)(void *)iface->ifa_addr)->sin_addr;
res = IF2IP_FOUND;
ip = curlx_inet_ntop(af, addr, ipstr, sizeof(ipstr));
curl_msnprintf(buf, buf_size, "%s%s", ip, scope);
result = curlx_inet_ntop(af, addr, ipstr, sizeof(ipstr));
curl_msnprintf(buf, buf_size, "%s%s", result ? "" : ipstr, scope);
break;
}
}
@ -188,7 +188,7 @@ if2ip_result_t Curl_if2ip(int af,
struct sockaddr_in *s;
curl_socket_t dummy;
size_t len;
const char *r;
CURLcode result;
#ifdef USE_IPV6
(void)remote_scope;
@ -228,10 +228,10 @@ if2ip_result_t Curl_if2ip(int af,
s = (struct sockaddr_in *)(void *)&req.ifr_addr;
memcpy(&in, &s->sin_addr, sizeof(in));
r = curlx_inet_ntop(s->sin_family, &in, buf, buf_size);
result = curlx_inet_ntop(s->sin_family, &in, buf, buf_size);
sclose(dummy);
if(!r)
if(result)
return IF2IP_NOT_FOUND;
return IF2IP_FOUND;
}

View file

@ -467,7 +467,7 @@ UNITTEST CURLUcode ipv6_parse(struct Curl_URL *u, char *hostname,
hostname[hlen] = 0; /* end the address there */
if(curlx_inet_pton(AF_INET6, hostname, dest) != 1)
return CURLUE_BAD_IPV6;
if(curlx_inet_ntop(AF_INET6, dest, hostname, hlen + 1)) {
if(!curlx_inet_ntop(AF_INET6, dest, hostname, hlen + 1)) {
hlen = strlen(hostname); /* might be shorter now */
hostname[hlen + 1] = 0;
}

View file

@ -82,7 +82,7 @@ static CURLcode httpsrr_print_addr(struct dynbuf *dyn,
CURLcode result = CURLE_OK;
for(i = 0; (i < (total_len / alen)) && !result; ++i) {
if(!curlx_inet_ntop(ai_family, addr + (i * alen), buf, sizeof(buf)))
if(curlx_inet_ntop(ai_family, addr + (i * alen), buf, sizeof(buf)))
result = curlx_dyn_add(dyn, "<error parsing address>");
else
result = curlx_dyn_addf(dyn, "%s%s", sep, buf);