curl: add support for HTTP authentication parameters

If connecting to a web server which has authentication
turned on, QEMU gets a 401 as curl has not been configured
with any authentication credentials.

This adds 4 new parameters to the curl block driver
options 'username', 'password-secret', 'proxy-username'
and 'proxy-password-secret'. Passwords are provided using
the recently added 'secret' object type

 $QEMU \
     -object secret,id=sec0,filename=/home/berrange/example.pw \
     -object secret,id=sec1,filename=/home/berrange/proxy.pw \
     -drive driver=http,url=http://example.com/some.img,\
            username=dan,password-secret=sec0,\
            proxy-username=dan,proxy-password-secret=sec1

Of course it is possible to use the same secret for both the
proxy & server passwords if desired, or omit the proxy auth
details, or the server auth details as required.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1453385961-10718-3-git-send-email-berrange@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>

block/curl.c

@@ -27,6 +27,7 @@
 #include "block/block_int.h"
 #include "qapi/qmp/qbool.h"
 #include "qapi/qmp/qstring.h"
+#include "crypto/secret.h"
 #include <curl/curl.h>
 
 // #define DEBUG_CURL
@@ -78,6 +79,10 @@ static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
 #define CURL_BLOCK_OPT_COOKIE    "cookie"
+#define CURL_BLOCK_OPT_USERNAME "username"
+#define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
+#define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
+#define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
 
 struct BDRVCURLState;
 
@@ -120,6 +125,10 @@ typedef struct BDRVCURLState {
     char *cookie;
     bool accept_range;
     AioContext *aio_context;
+    char *username;
+    char *password;
+    char *proxyusername;
+    char *proxypassword;
 } BDRVCURLState;
 
 static void curl_clean_state(CURLState *s);
@@ -419,6 +428,21 @@ static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 
+        if (s->username) {
+            curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
+        }
+        if (s->password) {
+            curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
+        }
+        if (s->proxyusername) {
+            curl_easy_setopt(state->curl,
+                             CURLOPT_PROXYUSERNAME, s->proxyusername);
+        }
+        if (s->proxypassword) {
+            curl_easy_setopt(state->curl,
+                             CURLOPT_PROXYPASSWORD, s->proxypassword);
+        }
+
         /* Restrict supported protocols to avoid security issues in the more
          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
          * CVE-2013-0249.
@@ -525,10 +549,31 @@ static QemuOptsList runtime_opts = {
             .type = QEMU_OPT_STRING,
             .help = "Pass the cookie or list of cookies with each request"
         },
+        {
+            .name = CURL_BLOCK_OPT_USERNAME,
+            .type = QEMU_OPT_STRING,
+            .help = "Username for HTTP auth"
+        },
+        {
+            .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
+            .type = QEMU_OPT_STRING,
+            .help = "ID of secret used as password for HTTP auth",
+        },
+        {
+            .name = CURL_BLOCK_OPT_PROXY_USERNAME,
+            .type = QEMU_OPT_STRING,
+            .help = "Username for HTTP proxy auth"
+        },
+        {
+            .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
+            .type = QEMU_OPT_STRING,
+            .help = "ID of secret used as password for HTTP proxy auth",
+        },
         { /* end of list */ }
     },
 };
 
+
 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
                      Error **errp)
 {
@@ -539,6 +584,7 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
     const char *file;
     const char *cookie;
     double d;
+    const char *secretid;
 
     static int inited = 0;
 
@@ -580,6 +626,26 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
         goto out_noclean;
     }
 
+    s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
+    secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
+
+    if (secretid) {
+        s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
+        if (!s->password) {
+            goto out_noclean;
+        }
+    }
+
+    s->proxyusername = g_strdup(
+        qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
+    secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
+    if (secretid) {
+        s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
+        if (!s->proxypassword) {
+            goto out_noclean;
+        }
+    }
+
     if (!inited) {
         curl_global_init(CURL_GLOBAL_ALL);
         inited = 1;