freebsd-skq/lib/libfetch/common.c
Dag-Erling Smørgrav 9c1ca3a1dd r261230 broke the cases where the amount of data to be read is not
known in advance, or where the caller doesn't care and just keeps
reading until it hits EOF.

In fetch_read(): the socket is non-blocking, so read() will return 0
on EOF, and -1 (errno == EAGAIN) when the connection is still open but
there is no data waiting.  In the first case, we should immediately
return 0.  The EINTR case was also broken, although not in a way that
matters.

In fetch_writev(): use timersub() and timercmp() as in fetch_read().

In http_fillbuf(): set errno to a sensible value when an invalid chunk
header is encountered.

In http_readfn(): as in fetch_read(), a zero return from down the
stack indicates EOF, not an error.  Furthermore, when io->error is
EINTR, clear it (but no errno) before returning so the caller can
retry after dealing with the interrupt.

MFC after:	3 days
2014-01-29 12:48:19 +00:00

1375 lines
32 KiB
C

/*-
* Copyright (c) 1998-2011 Dag-Erling Smørgrav
* Copyright (c) 2013 Michael Gmelin <freebsd@grem.de>
* 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("$FreeBSD$");
#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
static 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);
}
#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
if (conn->ssl != NULL)
rlen = fetch_ssl_read(conn->ssl, buf, len);
else
#endif
rlen = fetch_socket_read(conn->sd, buf, len);
if (rlen >= 0) {
break;
} else if (rlen == FETCH_READ_ERROR) {
fetch_syserr();
return (-1);
}
// assert(rlen == FETCH_READ_WAIT);
if (fetchTimeout > 0) {
gettimeofday(&now, NULL);
if (!timercmp(&timeout, &now, >)) {
errno = ETIMEDOUT;
fetch_syserr();
return (-1);
}
timersub(&timeout, &now, &delta);
deltams = delta.tv_sec * 1000 +
delta.tv_usec / 1000;;
}
errno = 0;
pfd.revents = 0;
if (poll(&pfd, 1, deltams) < 0) {
if (errno == EINTR && fetchRestartCalls)
continue;
fetch_syserr();
return (-1);
}
}
return (rlen);
}
/*
* Read a line of text from a connection w/ timeout
*/
#define MIN_BUF_SIZE 1024
int
fetch_getln(conn_t *conn)
{
char *tmp;
size_t tmpsize;
ssize_t len;
char c;
if (conn->buf == NULL) {
if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
errno = ENOMEM;
return (-1);
}
conn->bufsize = MIN_BUF_SIZE;
}
conn->buf[0] = '\0';
conn->buflen = 0;
do {
len = fetch_read(conn, &c, 1);
if (len == -1)
return (-1);
if (len == 0)
break;
conn->buf[conn->buflen++] = c;
if (conn->buflen == conn->bufsize) {
tmp = conn->buf;
tmpsize = conn->bufsize * 2 + 1;
if ((tmp = realloc(tmp, tmpsize)) == NULL) {
errno = ENOMEM;
return (-1);
}
conn->buf = tmp;
conn->bufsize = tmpsize;
}
} while (c != '\n');
conn->buf[conn->buflen] = '\0';
DEBUG(fprintf(stderr, "<<< %s", conn->buf));
return (0);
}
/*
* Write to a connection w/ timeout
*/
ssize_t
fetch_write(conn_t *conn, const char *buf, size_t len)
{
struct iovec iov;
iov.iov_base = __DECONST(char *, buf);
iov.iov_len = len;
return fetch_writev(conn, &iov, 1);
}
/*
* Write a vector to a connection w/ timeout
* Note: can modify the iovec.
*/
ssize_t
fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
{
struct timeval now, timeout, delta;
struct pollfd pfd;
ssize_t wlen, total;
int deltams;
memset(&pfd, 0, sizeof pfd);
if (fetchTimeout) {
pfd.fd = conn->sd;
pfd.events = POLLOUT | POLLERR;
gettimeofday(&timeout, NULL);
timeout.tv_sec += fetchTimeout;
}
total = 0;
while (iovcnt > 0) {
while (fetchTimeout && pfd.revents == 0) {
gettimeofday(&now, NULL);
if (!timercmp(&timeout, &now, >)) {
errno = ETIMEDOUT;
fetch_syserr();
return (-1);
}
timersub(&timeout, &now, &delta);
deltams = delta.tv_sec * 1000 +
delta.tv_usec / 1000;
errno = 0;
pfd.revents = 0;
if (poll(&pfd, 1, deltams) < 0) {
if (errno == EINTR && fetchRestartCalls)
continue;
return (-1);
}
}
errno = 0;
#ifdef WITH_SSL
if (conn->ssl != NULL)
wlen = SSL_write(conn->ssl,
iov->iov_base, iov->iov_len);
else
#endif
wlen = writev(conn->sd, iov, iovcnt);
if (wlen == 0) {
/* we consider a short write a failure */
/* XXX perhaps we shouldn't in the SSL case */
errno = EPIPE;
fetch_syserr();
return (-1);
}
if (wlen < 0) {
if (errno == EINTR && fetchRestartCalls)
continue;
return (-1);
}
total += wlen;
while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
wlen -= iov->iov_len;
iov++;
iovcnt--;
}
if (iovcnt > 0) {
iov->iov_len -= wlen;
iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
}
}
return (total);
}
/*
* Write a line of text to a connection w/ timeout
*/
int
fetch_putln(conn_t *conn, const char *str, size_t len)
{
struct iovec iov[2];
int ret;
DEBUG(fprintf(stderr, ">>> %s\n", str));
iov[0].iov_base = __DECONST(char *, str);
iov[0].iov_len = len;
iov[1].iov_base = __DECONST(char *, ENDL);
iov[1].iov_len = sizeof(ENDL);
if (len == 0)
ret = fetch_writev(conn, &iov[1], 1);
else
ret = fetch_writev(conn, iov, 2);
if (ret == -1)
return (-1);
return (0);
}
/*
* Close connection
*/
int
fetch_close(conn_t *conn)
{
int ret;
if (--conn->ref > 0)
return (0);
#ifdef WITH_SSL
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
ret = close(conn->sd);
free(conn->buf);
free(conn);
return (ret);
}
/*** Directory-related utility functions *************************************/
int
fetch_add_entry(struct url_ent **p, int *size, int *len,
const char *name, struct url_stat *us)
{
struct url_ent *tmp;
if (*p == NULL) {
*size = 0;
*len = 0;
}
if (*len >= *size - 1) {
tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p));
if (tmp == NULL) {
errno = ENOMEM;
fetch_syserr();
return (-1);
}
*size = (*size * 2 + 1);
*p = tmp;
}
tmp = *p + *len;
snprintf(tmp->name, PATH_MAX, "%s", name);
memcpy(&tmp->stat, us, sizeof(*us));
(*len)++;
(++tmp)->name[0] = 0;
return (0);
}
/*** Authentication-related utility functions ********************************/
static const char *
fetch_read_word(FILE *f)
{
static char word[1024];
if (fscanf(f, " %1023s ", word) != 1)
return (NULL);
return (word);
}
/*
* Get authentication data for a URL from .netrc
*/
int
fetch_netrc_auth(struct url *url)
{
char fn[PATH_MAX];
const char *word;
char *p;
FILE *f;
if ((p = getenv("NETRC")) != NULL) {
if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) {
fetch_info("$NETRC specifies a file name "
"longer than PATH_MAX");
return (-1);
}
} else {
if ((p = getenv("HOME")) != NULL) {
struct passwd *pwd;
if ((pwd = getpwuid(getuid())) == NULL ||
(p = pwd->pw_dir) == NULL)
return (-1);
}
if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn))
return (-1);
}
if ((f = fopen(fn, "r")) == NULL)
return (-1);
while ((word = fetch_read_word(f)) != NULL) {
if (strcmp(word, "default") == 0) {
DEBUG(fetch_info("Using default .netrc settings"));
break;
}
if (strcmp(word, "machine") == 0 &&
(word = fetch_read_word(f)) != NULL &&
strcasecmp(word, url->host) == 0) {
DEBUG(fetch_info("Using .netrc settings for %s", word));
break;
}
}
if (word == NULL)
goto ferr;
while ((word = fetch_read_word(f)) != NULL) {
if (strcmp(word, "login") == 0) {
if ((word = fetch_read_word(f)) == NULL)
goto ferr;
if (snprintf(url->user, sizeof(url->user),
"%s", word) > (int)sizeof(url->user)) {
fetch_info("login name in .netrc is too long");
url->user[0] = '\0';
}
} else if (strcmp(word, "password") == 0) {
if ((word = fetch_read_word(f)) == NULL)
goto ferr;
if (snprintf(url->pwd, sizeof(url->pwd),
"%s", word) > (int)sizeof(url->pwd)) {
fetch_info("password in .netrc is too long");
url->pwd[0] = '\0';
}
} else if (strcmp(word, "account") == 0) {
if ((word = fetch_read_word(f)) == NULL)
goto ferr;
/* XXX not supported! */
} else {
break;
}
}
fclose(f);
return (0);
ferr:
fclose(f);
return (-1);
}
/*
* The no_proxy environment variable specifies a set of domains for
* which the proxy should not be consulted; the contents is a comma-,
* or space-separated list of domain names. A single asterisk will
* override all proxy variables and no transactions will be proxied
* (for compatability with lynx and curl, see the discussion at
* <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>).
*/
int
fetch_no_proxy_match(const char *host)
{
const char *no_proxy, *p, *q;
size_t h_len, d_len;
if ((no_proxy = getenv("NO_PROXY")) == NULL &&
(no_proxy = getenv("no_proxy")) == NULL)
return (0);
/* asterisk matches any hostname */
if (strcmp(no_proxy, "*") == 0)
return (1);
h_len = strlen(host);
p = no_proxy;
do {
/* position p at the beginning of a domain suffix */
while (*p == ',' || isspace((unsigned char)*p))
p++;
/* position q at the first separator character */
for (q = p; *q; ++q)
if (*q == ',' || isspace((unsigned char)*q))
break;
d_len = q - p;
if (d_len > 0 && h_len >= d_len &&
strncasecmp(host + h_len - d_len,
p, d_len) == 0) {
/* domain name matches */
return (1);
}
p = q + 1;
} while (*q);
return (0);
}