libcurl: add SASL security patch

Fixes CVE-2013-0249, see http://curl.haxx.se/docs/adv_20130206.html

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

diff --git a/package/libcurl/libcurl-cve-2013-0249.patch b/package/libcurl/libcurl-cve-2013-0249.patch
new file mode 100644 (file)
index 0000000..7d2af2a
--- /dev/null
+++ b/package/libcurl/libcurl-cve-2013-0249.patch
@@ -0,0 +1,65 @@
+From ee45a34907ffeb5fd95b0513040d8491d565b663 Mon Sep 17 00:00:00 2001
+From: Eldar Zaitov <kyprizel@volema.com>
+Date: Wed, 30 Jan 2013 23:22:27 +0100
+Subject: [PATCH] Curl_sasl_create_digest_md5_message: fix buffer overflow
+
+When negotiating SASL DIGEST-MD5 authentication, the function
+Curl_sasl_create_digest_md5_message() uses the data provided from the
+server without doing the proper length checks and that data is then
+appended to a local fixed-size buffer on the stack.
+
+This vulnerability can be exploited by someone who is in control of a
+server that a libcurl based program is accessing with POP3, SMTP or
+IMAP. For applications that accept user provided URLs, it is also
+thinkable that a malicious user would feed an application with a URL to
+a server hosting code targetting this flaw.
+
+Bug: http://curl.haxx.se/docs/adv_20130206.html
+---
+ lib/curl_sasl.c |   23 ++++++-----------------
+ 1 file changed, 6 insertions(+), 17 deletions(-)
+
+diff --git a/lib/curl_sasl.c b/lib/curl_sasl.c
+index 57116b6..d07387d 100644
+--- a/lib/curl_sasl.c
++++ b/lib/curl_sasl.c
+@@ -346,9 +346,7 @@ CURLcode Curl_sasl_create_digest_md5_message(struct SessionHandle *data,
+     snprintf(&HA1_hex[2 * i], 3, "%02x", digest[i]);
+ 
+   /* Prepare the URL string */
+-  strcpy(uri, service);
+-  strcat(uri, "/");
+-  strcat(uri, realm);
++  snprintf(uri, sizeof(uri), "%s/%s", service, realm);
+ 
+   /* Calculate H(A2) */
+   ctxt = Curl_MD5_init(Curl_DIGEST_MD5);
+@@ -392,20 +390,11 @@ CURLcode Curl_sasl_create_digest_md5_message(struct SessionHandle *data,
+   for(i = 0; i < MD5_DIGEST_LEN; i++)
+     snprintf(&resp_hash_hex[2 * i], 3, "%02x", digest[i]);
+ 
+-  strcpy(response, "username=\"");
+-  strcat(response, userp);
+-  strcat(response, "\",realm=\"");
+-  strcat(response, realm);
+-  strcat(response, "\",nonce=\"");
+-  strcat(response, nonce);
+-  strcat(response, "\",cnonce=\"");
+-  strcat(response, cnonce);
+-  strcat(response, "\",nc=");
+-  strcat(response, nonceCount);
+-  strcat(response, ",digest-uri=\"");
+-  strcat(response, uri);
+-  strcat(response, "\",response=");
+-  strcat(response, resp_hash_hex);
++  snprintf(response, sizeof(response),
++           "username=\"%s\",realm=\"%s\",nonce=\"%s\","
++           "cnonce=\"%s\",nc=\"%s\",digest-uri=\"%s\",response=%s",
++           userp, realm, nonce,
++           cnonce, nonceCount, uri, resp_hash_hex);
+ 
+   /* Base64 encode the reply */
+   return Curl_base64_encode(data, response, 0, outptr, outlen);
+-- 
+1.7.10.4
+