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common.c
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/*-
* Copyright (c) 1998-2014 Dag-Erling Smørgrav
* Copyright (c) 2013 Michael Gmelin <[email protected]>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: stable/10/lib/libfetch/common.c 262560 2014-02-27 13:27:04Z des $");
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <poll.h>
#include <pwd.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#ifdef WITH_SSL
#include <openssl/x509v3.h>
#endif
#include "fetch.h"
#include "common.h"
/*** Local data **************************************************************/
/*
* Error messages for resolver errors
*/
static struct fetcherr netdb_errlist[] = {
#ifdef EAI_NODATA
{ EAI_NODATA, FETCH_RESOLV, "Host not found" },
#endif
{ EAI_AGAIN, FETCH_TEMP, "Transient resolver failure" },
{ EAI_FAIL, FETCH_RESOLV, "Non-recoverable resolver failure" },
{ EAI_NONAME, FETCH_RESOLV, "No address record" },
{ -1, FETCH_UNKNOWN, "Unknown resolver error" }
};
/* End-of-Line */
static const char ENDL[2] = "\r\n";
/*** Error-reporting functions ***********************************************/
/*
* Map error code to string
*/
static struct fetcherr *
fetch_finderr(struct fetcherr *p, int e)
{
while (p->num != -1 && p->num != e)
p++;
return (p);
}
/*
* Set error code
*/
void
fetch_seterr(struct fetcherr *p, int e)
{
p = fetch_finderr(p, e);
fetchLastErrCode = p->cat;
snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
}
/*
* Set error code according to errno
*/
void
fetch_syserr(void)
{
switch (errno) {
case 0:
fetchLastErrCode = FETCH_OK;
break;
case EPERM:
case EACCES:
case EROFS:
case EAUTH:
case ENEEDAUTH:
fetchLastErrCode = FETCH_AUTH;
break;
case ENOENT:
case EISDIR: /* XXX */
fetchLastErrCode = FETCH_UNAVAIL;
break;
case ENOMEM:
fetchLastErrCode = FETCH_MEMORY;
break;
case EBUSY:
case EAGAIN:
fetchLastErrCode = FETCH_TEMP;
break;
case EEXIST:
fetchLastErrCode = FETCH_EXISTS;
break;
case ENOSPC:
fetchLastErrCode = FETCH_FULL;
break;
case EADDRINUSE:
case EADDRNOTAVAIL:
case ENETDOWN:
case ENETUNREACH:
case ENETRESET:
case EHOSTUNREACH:
fetchLastErrCode = FETCH_NETWORK;
break;
case ECONNABORTED:
case ECONNRESET:
fetchLastErrCode = FETCH_ABORT;
break;
case ETIMEDOUT:
fetchLastErrCode = FETCH_TIMEOUT;
break;
case ECONNREFUSED:
case EHOSTDOWN:
fetchLastErrCode = FETCH_DOWN;
break;
default:
fetchLastErrCode = FETCH_UNKNOWN;
}
snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
}
/*
* Emit status message
*/
void
fetch_info(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
fputc('\n', stderr);
}
/*** Network-related utility functions ***************************************/
/*
* Return the default port for a scheme
*/
int
fetch_default_port(const char *scheme)
{
struct servent *se;
if ((se = getservbyname(scheme, "tcp")) != NULL)
return (ntohs(se->s_port));
if (strcasecmp(scheme, SCHEME_FTP) == 0)
return (FTP_DEFAULT_PORT);
if (strcasecmp(scheme, SCHEME_HTTP) == 0)
return (HTTP_DEFAULT_PORT);
return (0);
}
/*
* Return the default proxy port for a scheme
*/
int
fetch_default_proxy_port(const char *scheme)
{
if (strcasecmp(scheme, SCHEME_FTP) == 0)
return (FTP_DEFAULT_PROXY_PORT);
if (strcasecmp(scheme, SCHEME_HTTP) == 0)
return (HTTP_DEFAULT_PROXY_PORT);
return (0);
}
/*
* Create a connection for an existing descriptor.
*/
conn_t *
fetch_reopen(int sd)
{
conn_t *conn;
int opt = 1;
/* allocate and fill connection structure */
if ((conn = calloc(1, sizeof(*conn))) == NULL)
return (NULL);
fcntl(sd, F_SETFD, FD_CLOEXEC);
setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt);
conn->sd = sd;
++conn->ref;
return (conn);
}
/*
* Bump a connection's reference count.
*/
conn_t *
fetch_ref(conn_t *conn)
{
++conn->ref;
return (conn);
}
/*
* Bind a socket to a specific local address
*/
int
fetch_bind(int sd, int af, const char *addr)
{
struct addrinfo hints, *res, *res0;
int err;
memset(&hints, 0, sizeof(hints));
hints.ai_family = af;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
if ((err = getaddrinfo(addr, NULL, &hints, &res0)) != 0)
return (-1);
for (res = res0; res; res = res->ai_next)
if (bind(sd, res->ai_addr, res->ai_addrlen) == 0)
return (0);
return (-1);
}
/*
* Establish a TCP connection to the specified port on the specified host.
*/
conn_t *
fetch_connect(const char *host, int port, int af, int verbose)
{
conn_t *conn;
char pbuf[10];
const char *bindaddr;
struct addrinfo hints, *res, *res0;
int sd, err;
DEBUG(fprintf(stderr, "---> %s:%d\n", host, port));
if (verbose)
fetch_info("looking up %s", host);
/* look up host name and set up socket address structure */
snprintf(pbuf, sizeof(pbuf), "%d", port);
memset(&hints, 0, sizeof(hints));
hints.ai_family = af;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) {
netdb_seterr(err);
return (NULL);
}
bindaddr = getenv("FETCH_BIND_ADDRESS");
if (verbose)
fetch_info("connecting to %s:%d", host, port);
/* try to connect */
for (sd = -1, res = res0; res; sd = -1, res = res->ai_next) {
if ((sd = socket(res->ai_family, res->ai_socktype,
res->ai_protocol)) == -1)
continue;
if (bindaddr != NULL && *bindaddr != '\0' &&
fetch_bind(sd, res->ai_family, bindaddr) != 0) {
fetch_info("failed to bind to '%s'", bindaddr);
close(sd);
continue;
}
if (connect(sd, res->ai_addr, res->ai_addrlen) == 0 &&
fcntl(sd, F_SETFL, O_NONBLOCK) == 0)
break;
close(sd);
}
freeaddrinfo(res0);
if (sd == -1) {
fetch_syserr();
return (NULL);
}
if ((conn = fetch_reopen(sd)) == NULL) {
fetch_syserr();
close(sd);
}
return (conn);
}
#ifdef WITH_SSL
/*
* Convert characters A-Z to lowercase (intentionally avoid any locale
* specific conversions).
*/
static char
fetch_ssl_tolower(char in)
{
if (in >= 'A' && in <= 'Z')
return (in + 32);
else
return (in);
}
/*
* isalpha implementation that intentionally avoids any locale specific
* conversions.
*/
static int
fetch_ssl_isalpha(char in)
{
return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z'));
}
/*
* Check if passed hostnames a and b are equal.
*/
static int
fetch_ssl_hname_equal(const char *a, size_t alen, const char *b,
size_t blen)
{
size_t i;
if (alen != blen)
return (0);
for (i = 0; i < alen; ++i) {
if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i]))
return (0);
}
return (1);
}
/*
* Check if domain label is traditional, meaning that only A-Z, a-z, 0-9
* and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha-
* numeric characters. Double hyphens (like they're found in IDN a-labels
* 'xn--') are not allowed. Empty labels are invalid.
*/
static int
fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok)
{
size_t i;
if (!len || l[0] == '-' || l[len-1] == '-')
return (0);
for (i = 0; i < len; ++i) {
if (!isdigit(l[i]) &&
!fetch_ssl_isalpha(l[i]) &&
!(l[i] == '*' && wcok) &&
!(l[i] == '-' && l[i - 1] != '-'))
return (0);
}
return (1);
}
/*
* Check if host name consists only of numbers. This might indicate an IP
* address, which is not a good idea for CN wildcard comparison.
*/
static int
fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len)
{
size_t i;
for (i = 0; i < len; ++i) {
if (!((hostname[i] >= '0' && hostname[i] <= '9') ||
hostname[i] == '.'))
return (0);
}
return (1);
}
/*
* Check if the host name h passed matches the pattern passed in m which
* is usually part of subjectAltName or CN of a certificate presented to
* the client. This includes wildcard matching. The algorithm is based on
* RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280.
*/
static int
fetch_ssl_hname_match(const char *h, size_t hlen, const char *m,
size_t mlen)
{
int delta, hdotidx, mdot1idx, wcidx;
const char *hdot, *mdot1, *mdot2;
const char *wc; /* wildcard */
if (!(h && *h && m && *m))
return (0);
if ((wc = strnstr(m, "*", mlen)) == NULL)
return (fetch_ssl_hname_equal(h, hlen, m, mlen));
wcidx = wc - m;
/* hostname should not be just dots and numbers */
if (fetch_ssl_hname_is_only_numbers(h, hlen))
return (0);
/* only one wildcard allowed in pattern */
if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL)
return (0);
/*
* there must be at least two more domain labels and
* wildcard has to be in the leftmost label (RFC6125)
*/
mdot1 = strnstr(m, ".", mlen);
if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4)
return (0);
mdot1idx = mdot1 - m;
mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1);
if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2)
return (0);
/* hostname must contain a dot and not be the 1st char */
hdot = strnstr(h, ".", hlen);
if (hdot == NULL || hdot == h)
return (0);
hdotidx = hdot - h;
/*
* host part of hostname must be at least as long as
* pattern it's supposed to match
*/
if (hdotidx < mdot1idx)
return (0);
/*
* don't allow wildcards in non-traditional domain names
* (IDN, A-label, U-label...)
*/
if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) ||
!fetch_ssl_is_trad_domain_label(m, mdot1idx, 1))
return (0);
/* match domain part (part after first dot) */
if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1,
mlen - mdot1idx))
return (0);
/* match part left of wildcard */
if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx))
return (0);
/* match part right of wildcard */
delta = mdot1idx - wcidx - 1;
if (!fetch_ssl_hname_equal(hdot - delta, delta,
mdot1 - delta, delta))
return (0);
/* all tests succeded, it's a match */
return (1);
}
/*
* Get numeric host address info - returns NULL if host was not an IP
* address. The caller is responsible for deallocation using
* freeaddrinfo(3).
*/
static struct addrinfo *
fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len)
{
struct addrinfo hints, *res;
char *host;
host = (char *)malloc(len + 1);
memcpy(host, hostname, len);
host[len] = '\0';
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
hints.ai_flags = AI_NUMERICHOST;
/* port is not relevant for this purpose */
getaddrinfo(host, "443", &hints, &res);
free(host);
return res;
}
/*
* Compare ip address in addrinfo with address passes.
*/
static int
fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost,
size_t rhostlen)
{
const void *left;
if (lhost->ai_family == AF_INET && rhostlen == 4) {
left = (void *)&((struct sockaddr_in*)(void *)
lhost->ai_addr)->sin_addr.s_addr;
#ifdef INET6
} else if (lhost->ai_family == AF_INET6 && rhostlen == 16) {
left = (void *)&((struct sockaddr_in6 *)(void *)
lhost->ai_addr)->sin6_addr;
#endif
} else
return (0);
return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0);
}
/*
* Compare ip address in addrinfo with host passed. If host is not an IP
* address, comparison will fail.
*/
static int
fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r,
size_t rlen)
{
struct addrinfo *raddr;
int ret;
char *rip;
ret = 0;
if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL)
return 0; /* not a numeric host */
if (laddr->ai_family == raddr->ai_family) {
if (laddr->ai_family == AF_INET) {
rip = (char *)&((struct sockaddr_in *)(void *)
raddr->ai_addr)->sin_addr.s_addr;
ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4);
#ifdef INET6
} else if (laddr->ai_family == AF_INET6) {
rip = (char *)&((struct sockaddr_in6 *)(void *)
raddr->ai_addr)->sin6_addr;
ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16);
#endif
}
}
freeaddrinfo(raddr);
return (ret);
}
/*
* Verify server certificate by subjectAltName.
*/
static int
fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames,
const char *host, struct addrinfo *ip)
{
const GENERAL_NAME *name;
size_t nslen;
int i;
const char *ns;
for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) {
#if OPENSSL_VERSION_NUMBER < 0x10000000L
/*
* This is a workaround, since the following line causes
* alignment issues in clang:
* name = sk_GENERAL_NAME_value(altnames, i);
* OpenSSL explicitly warns not to use those macros
* directly, but there isn't much choice (and there
* shouldn't be any ill side effects)
*/
name = (GENERAL_NAME *)SKM_sk_value(void, altnames, i);
#else
name = sk_GENERAL_NAME_value(altnames, i);
#endif
ns = (const char *)ASN1_STRING_data(name->d.ia5);
nslen = (size_t)ASN1_STRING_length(name->d.ia5);
if (name->type == GEN_DNS && ip == NULL &&
fetch_ssl_hname_match(host, strlen(host), ns, nslen))
return (1);
else if (name->type == GEN_IPADD && ip != NULL &&
fetch_ssl_ipaddr_match_bin(ip, ns, nslen))
return (1);
}
return (0);
}
/*
* Verify server certificate by CN.
*/
static int
fetch_ssl_verify_cn(X509_NAME *subject, const char *host,
struct addrinfo *ip)
{
ASN1_STRING *namedata;
X509_NAME_ENTRY *nameentry;
int cnlen, lastpos, loc, ret;
unsigned char *cn;
ret = 0;
lastpos = -1;
loc = -1;
cn = NULL;
/* get most specific CN (last entry in list) and compare */
while ((lastpos = X509_NAME_get_index_by_NID(subject,
NID_commonName, lastpos)) != -1)
loc = lastpos;
if (loc > -1) {
nameentry = X509_NAME_get_entry(subject, loc);
namedata = X509_NAME_ENTRY_get_data(nameentry);
cnlen = ASN1_STRING_to_UTF8(&cn, namedata);
if (ip == NULL &&
fetch_ssl_hname_match(host, strlen(host), cn, cnlen))
ret = 1;
else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen))
ret = 1;
OPENSSL_free(cn);
}
return (ret);
}
/*
* Verify that server certificate subjectAltName/CN matches
* hostname. First check, if there are alternative subject names. If yes,
* those have to match. Only if those don't exist it falls back to
* checking the subject's CN.
*/
static int
fetch_ssl_verify_hname(X509 *cert, const char *host)
{
struct addrinfo *ip;
STACK_OF(GENERAL_NAME) *altnames;
X509_NAME *subject;
int ret;
ret = 0;
ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host));
altnames = X509_get_ext_d2i(cert, NID_subject_alt_name,
NULL, NULL);
if (altnames != NULL) {
ret = fetch_ssl_verify_altname(altnames, host, ip);
} else {
subject = X509_get_subject_name(cert);
if (subject != NULL)
ret = fetch_ssl_verify_cn(subject, host, ip);
}
if (ip != NULL)
freeaddrinfo(ip);
if (altnames != NULL)
GENERAL_NAMES_free(altnames);
return (ret);
}
/*
* Configure transport security layer based on environment.
*/
static void
fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose)
{
long ssl_ctx_options;
ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_TICKET;
if (getenv("SSL_ALLOW_SSL2") == NULL)
ssl_ctx_options |= SSL_OP_NO_SSLv2;
if (getenv("SSL_NO_SSL3") != NULL)
ssl_ctx_options |= SSL_OP_NO_SSLv3;
if (getenv("SSL_NO_TLS1") != NULL)
ssl_ctx_options |= SSL_OP_NO_TLSv1;
if (verbose)
fetch_info("SSL options: %lx", ssl_ctx_options);
SSL_CTX_set_options(ctx, ssl_ctx_options);
}
/*
* Configure peer verification based on environment.
*/
static int
fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose)
{
X509_LOOKUP *crl_lookup;
X509_STORE *crl_store;
const char *ca_cert_file, *ca_cert_path, *crl_file;
if (getenv("SSL_NO_VERIFY_PEER") == NULL) {
ca_cert_file = getenv("SSL_CA_CERT_FILE") != NULL ?
getenv("SSL_CA_CERT_FILE") : "/etc/ssl/cert.pem";
ca_cert_path = getenv("SSL_CA_CERT_PATH");
if (verbose) {
fetch_info("Peer verification enabled");
if (ca_cert_file != NULL)
fetch_info("Using CA cert file: %s",
ca_cert_file);
if (ca_cert_path != NULL)
fetch_info("Using CA cert path: %s",
ca_cert_path);
}
SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
fetch_ssl_cb_verify_crt);
SSL_CTX_load_verify_locations(ctx, ca_cert_file,
ca_cert_path);
if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) {
if (verbose)
fetch_info("Using CRL file: %s", crl_file);
crl_store = SSL_CTX_get_cert_store(ctx);
crl_lookup = X509_STORE_add_lookup(crl_store,
X509_LOOKUP_file());
if (crl_lookup == NULL ||
!X509_load_crl_file(crl_lookup, crl_file,
X509_FILETYPE_PEM)) {
fprintf(stderr,
"Could not load CRL file %s\n",
crl_file);
return (0);
}
X509_STORE_set_flags(crl_store,
X509_V_FLAG_CRL_CHECK |
X509_V_FLAG_CRL_CHECK_ALL);
}
}
return (1);
}
/*
* Configure client certificate based on environment.
*/
static int
fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose)
{
const char *client_cert_file, *client_key_file;
if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) {
client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ?
getenv("SSL_CLIENT_KEY_FILE") : client_cert_file;
if (verbose) {
fetch_info("Using client cert file: %s",
client_cert_file);
fetch_info("Using client key file: %s",
client_key_file);
}
if (SSL_CTX_use_certificate_chain_file(ctx,
client_cert_file) != 1) {
fprintf(stderr,
"Could not load client certificate %s\n",
client_cert_file);
return (0);
}
if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file,
SSL_FILETYPE_PEM) != 1) {
fprintf(stderr,
"Could not load client key %s\n",
client_key_file);
return (0);
}
}
return (1);
}
/*
* Callback for SSL certificate verification, this is called on server
* cert verification. It takes no decision, but informs the user in case
* verification failed.
*/
int
fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx)
{
X509 *crt;
X509_NAME *name;
char *str;
str = NULL;
if (!verified) {
if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL &&
(name = X509_get_subject_name(crt)) != NULL)
str = X509_NAME_oneline(name, 0, 0);
fprintf(stderr, "Certificate verification failed for %s\n",
str != NULL ? str : "no relevant certificate");
OPENSSL_free(str);
}
return (verified);
}
#endif
/*
* Enable SSL on a connection.
*/
int
fetch_ssl(conn_t *conn, const struct url *URL, int verbose)
{
#ifdef WITH_SSL
int ret, ssl_err;
X509_NAME *name;
char *str;
/* Init the SSL library and context */
if (!SSL_library_init()){
fprintf(stderr, "SSL library init failed\n");
return (-1);
}
SSL_load_error_strings();
conn->ssl_meth = SSLv23_client_method();
conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY);
fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose);
if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose))
return (-1);
if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose))
return (-1);
conn->ssl = SSL_new(conn->ssl_ctx);
if (conn->ssl == NULL) {
fprintf(stderr, "SSL context creation failed\n");
return (-1);
}
SSL_set_fd(conn->ssl, conn->sd);
#if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT)
if (!SSL_set_tlsext_host_name(conn->ssl,
__DECONST(struct url *, URL)->host)) {
fprintf(stderr,
"TLS server name indication extension failed for host %s\n",
URL->host);
return (-1);
}
#endif
while ((ret = SSL_connect(conn->ssl)) == -1) {
ssl_err = SSL_get_error(conn->ssl, ret);
if (ssl_err != SSL_ERROR_WANT_READ &&
ssl_err != SSL_ERROR_WANT_WRITE) {
ERR_print_errors_fp(stderr);
return (-1);
}
}
conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
if (conn->ssl_cert == NULL) {
fprintf(stderr, "No server SSL certificate\n");
return (-1);
}
if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) {
if (verbose)
fetch_info("Verify hostname");
if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) {
fprintf(stderr,
"SSL certificate subject doesn't match host %s\n",
URL->host);
return (-1);
}
}
if (verbose) {
fetch_info("SSL connection established using %s",
SSL_get_cipher(conn->ssl));
name = X509_get_subject_name(conn->ssl_cert);
str = X509_NAME_oneline(name, 0, 0);
fetch_info("Certificate subject: %s", str);
OPENSSL_free(str);
name = X509_get_issuer_name(conn->ssl_cert);
str = X509_NAME_oneline(name, 0, 0);
fetch_info("Certificate issuer: %s", str);
OPENSSL_free(str);
}
return (0);
#else
(void)conn;
(void)verbose;
fprintf(stderr, "SSL support disabled\n");
return (-1);
#endif
}
#define FETCH_READ_WAIT -2
#define FETCH_READ_ERROR -1
#define FETCH_READ_DONE 0
#ifdef WITH_SSL
ssize_t
fetch_ssl_read(SSL *ssl, char *buf, size_t len)
{
ssize_t rlen;
int ssl_err;
rlen = SSL_read(ssl, buf, len);
if (rlen < 0) {
ssl_err = SSL_get_error(ssl, rlen);
if (ssl_err == SSL_ERROR_WANT_READ ||
ssl_err == SSL_ERROR_WANT_WRITE) {
return (FETCH_READ_WAIT);
} else {
ERR_print_errors_fp(stderr);
return (FETCH_READ_ERROR);
}
}
return (rlen);
}
ssize_t
fetch_ssl_write(SSL *ssl, char *buf, size_t len)
{
return (SSL_write(ssl, buf, len));
}
void
fetch_ssl_shutdown(conn_t *conn)
{
if (conn->ssl) {
SSL_shutdown(conn->ssl);
SSL_set_connect_state(conn->ssl);
SSL_free(conn->ssl);
conn->ssl = NULL;
}
if (conn->ssl_ctx) {
SSL_CTX_free(conn->ssl_ctx);
conn->ssl_ctx = NULL;
}
if (conn->ssl_cert) {
X509_free(conn->ssl_cert);
conn->ssl_cert = NULL;
}
}
#endif
static ssize_t
fetch_socket_read(int sd, char *buf, size_t len)
{
ssize_t rlen;
rlen = read(sd, buf, len);
if (rlen < 0) {
if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls))
return (FETCH_READ_WAIT);
else
return (FETCH_READ_ERROR);
}
return (rlen);
}
/*
* Read a character from a connection w/ timeout
*/
ssize_t
fetch_read(conn_t *conn, char *buf, size_t len)
{
struct timeval now, timeout, delta;
struct pollfd pfd;
ssize_t rlen;
int deltams;
if (fetchTimeout > 0) {
gettimeofday(&timeout, NULL);
timeout.tv_sec += fetchTimeout;
}
deltams = INFTIM;
memset(&pfd, 0, sizeof pfd);
pfd.fd = conn->sd;
pfd.events = POLLIN | POLLERR;
for (;;) {
/*
* The socket is non-blocking. Instead of the canonical
* poll() -> read(), we do the following:
*
* 1) call read() or SSL_read().
* 2) if we received some data, return it.
* 3) if an error occurred, return -1.
* 4) if read() or SSL_read() signaled EOF, return.
* 5) if we did not receive any data but we're not at EOF,
* call poll().
*
* In the SSL case, this is necessary because if we
* receive a close notification, we have to call
* SSL_read() one additional time after we've read
* everything we received.
*
* In the non-SSL case, it may improve performance (very
* slightly) when reading small amounts of data.
*/
#ifdef WITH_SSL
#ifdef NO_SANDBOX