Use "==0" instead of "!strcmp" etc
[openssl.git] / ssl / d1_srtp.c
index 928935b..9932dde 100644 (file)
@@ -5,21 +5,21 @@
  * This package is an SSL implementation written
  * by Eric Young (eay@cryptsoft.com).
  * The implementation was written so as to conform with Netscapes SSL.
- * 
+ *
  * This library is free for commercial and non-commercial use as long as
  * the following conditions are aheared to.  The following conditions
  * apply to all code found in this distribution, be it the RC4, RSA,
  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  * included with this distribution is covered by the same copyright terms
  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- * 
+ *
  * Copyright remains Eric Young's, and as such any Copyright notices in
  * the code are not to be removed.
  * If this package is used in a product, Eric Young should be given attribution
  * as the author of the parts of the library used.
  * This can be in the form of a textual message at program startup or
  * in documentation (online or textual) provided with the package.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *     Eric Young (eay@cryptsoft.com)"
  *    The word 'cryptographic' can be left out if the rouines from the library
  *    being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from 
+ * 4. If you include any Windows specific code (or a derivative thereof) from
  *    the apps directory (application code) you must include an acknowledgement:
  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
@@ -49,7 +49,7 @@
  * 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.
- * 
+ *
  * The licence and distribution terms for any publically available version or
  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  * copied and put under another distribution licence
@@ -63,7 +63,7 @@
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer. 
+ *    notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *
  */
 /*
-  DTLS code by Eric Rescorla <ekr@rtfm.com>
-
-  Copyright (C) 2006, Network Resonance, Inc.
-  Copyright (C) 2011, RTFM, Inc.
-*/
-
-#ifndef OPENSSL_NO_SRTP
+ * DTLS code by Eric Rescorla <ekr@rtfm.com>
+ *
+ * Copyright (C) 2006, Network Resonance, Inc. Copyright (C) 2011, RTFM, Inc.
+ */
 
 #include <stdio.h>
 #include <openssl/objects.h>
 #include "ssl_locl.h"
-#include "srtp.h"
 
+#ifndef OPENSSL_NO_SRTP
 
-static SRTP_PROTECTION_PROFILE srtp_known_profiles[]=
-    {
-    {
-    "SRTP_AES128_CM_SHA1_80",
-    SRTP_AES128_CM_SHA1_80,
-    },
-    {
-    "SRTP_AES128_CM_SHA1_32",
-    SRTP_AES128_CM_SHA1_32,
-    },
-#if 0
+static SRTP_PROTECTION_PROFILE srtp_known_profiles[] = {
     {
-    "SRTP_NULL_SHA1_80",
-    SRTP_NULL_SHA1_80,
-    },
+     "SRTP_AES128_CM_SHA1_80",
+     SRTP_AES128_CM_SHA1_80,
+     },
     {
-    "SRTP_NULL_SHA1_32",
-    SRTP_NULL_SHA1_32,
-    },
-#endif
+     "SRTP_AES128_CM_SHA1_32",
+     SRTP_AES128_CM_SHA1_32,
+     },
     {0}
-    };
+};
 
 static int find_profile_by_name(char *profile_name,
-                               SRTP_PROTECTION_PROFILE **pptr,unsigned len)
-       {
-       SRTP_PROTECTION_PROFILE *p;
-
-       p=srtp_known_profiles;
-       while(p->name)
-               {
-               if((len == strlen(p->name)) && !strncmp(p->name,profile_name,
-                                                       len))
-                       {
-                       *pptr=p;
-                       return 0;
-                       }
-
-               p++;
-               }
-
-       return 1;
-       }
-
-static int find_profile_by_num(unsigned profile_num,
-                              SRTP_PROTECTION_PROFILE **pptr)
-       {
-       SRTP_PROTECTION_PROFILE *p;
-
-       p=srtp_known_profiles;
-       while(p->name)
-               {
-               if(p->id == profile_num)
-                       {
-                       *pptr=p;
-                       return 0;
-                       }
-               p++;
-               }
-
-       return 1;
-       }
-
-static int ssl_ctx_make_profiles(const char *profiles_string,STACK_OF(SRTP_PROTECTION_PROFILE) **out)
-       {
-       STACK_OF(SRTP_PROTECTION_PROFILE) *profiles;
-
-       char *col;
-       char *ptr=(char *)profiles_string;
-    
-       SRTP_PROTECTION_PROFILE *p;
-
-       if(!(profiles=sk_SRTP_PROTECTION_PROFILE_new_null()))
-               {
-               SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES, SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES);
-               return 1;
-               }
-    
-       do
-               {
-               col=strchr(ptr,':');
-
-               if(!find_profile_by_name(ptr,&p,
-                                        col ? col-ptr : (int)strlen(ptr)))
-                       {
-                       sk_SRTP_PROTECTION_PROFILE_push(profiles,p);
-                       }
-               else
-                       {
-                       SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE);
-                       return 1;
-                       }
-
-               if(col) ptr=col+1;
-               } while (col);
-
-       *out=profiles;
-    
-       return 0;
-       }
-    
-int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx,const char *profiles)
-       {
-       return ssl_ctx_make_profiles(profiles,&ctx->srtp_profiles);
-       }
-
-int SSL_set_tlsext_use_srtp(SSL *s,const char *profiles)
-       {
-       return ssl_ctx_make_profiles(profiles,&s->srtp_profiles);
-       }
-
+                                SRTP_PROTECTION_PROFILE **pptr, unsigned len)
+{
+    SRTP_PROTECTION_PROFILE *p;
+
+    p = srtp_known_profiles;
+    while (p->name) {
+        if ((len == strlen(p->name))
+            && strncmp(p->name, profile_name, len) == 0) {
+            *pptr = p;
+            return 0;
+        }
+
+        p++;
+    }
+
+    return 1;
+}
+
+static int ssl_ctx_make_profiles(const char *profiles_string,
+                                 STACK_OF(SRTP_PROTECTION_PROFILE) **out)
+{
+    STACK_OF(SRTP_PROTECTION_PROFILE) *profiles;
+
+    char *col;
+    char *ptr = (char *)profiles_string;
+    SRTP_PROTECTION_PROFILE *p;
+
+    if (!(profiles = sk_SRTP_PROTECTION_PROFILE_new_null())) {
+        SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
+               SSL_R_SRTP_COULD_NOT_ALLOCATE_PROFILES);
+        return 1;
+    }
+
+    do {
+        col = strchr(ptr, ':');
+
+        if (!find_profile_by_name(ptr, &p,
+                                  col ? col - ptr : (int)strlen(ptr))) {
+            if (sk_SRTP_PROTECTION_PROFILE_find(profiles, p) >= 0) {
+                SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
+                       SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+                sk_SRTP_PROTECTION_PROFILE_free(profiles);
+                return 1;
+            }
+
+            sk_SRTP_PROTECTION_PROFILE_push(profiles, p);
+        } else {
+            SSLerr(SSL_F_SSL_CTX_MAKE_PROFILES,
+                   SSL_R_SRTP_UNKNOWN_PROTECTION_PROFILE);
+            sk_SRTP_PROTECTION_PROFILE_free(profiles);
+            return 1;
+        }
+
+        if (col)
+            ptr = col + 1;
+    } while (col);
+
+    *out = profiles;
+
+    return 0;
+}
+
+int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles)
+{
+    return ssl_ctx_make_profiles(profiles, &ctx->srtp_profiles);
+}
+
+int SSL_set_tlsext_use_srtp(SSL *s, const char *profiles)
+{
+    return ssl_ctx_make_profiles(profiles, &s->srtp_profiles);
+}
 
 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *s)
-       {
-       if(s != NULL)
-               {
-               if(s->srtp_profiles != NULL)
-                       {
-                       return s->srtp_profiles;
-                       }
-               else if((s->ctx != NULL) &&
-                       (s->ctx->srtp_profiles != NULL))
-                       {
-                       return s->ctx->srtp_profiles;
-                       }
-               }
-
-       return NULL;
-       }
+{
+    if (s != NULL) {
+        if (s->srtp_profiles != NULL) {
+            return s->srtp_profiles;
+        } else if ((s->ctx != NULL) && (s->ctx->srtp_profiles != NULL)) {
+            return s->ctx->srtp_profiles;
+        }
+    }
+
+    return NULL;
+}
 
 SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s)
-       {
-       return s->srtp_profile;
-       }
-
-/* Note: this function returns 0 length if there are no 
-   profiles specified */
-int ssl_add_clienthello_use_srtp_ext(SSL *s, unsigned char *p, int *len, int maxlen)
-       {
-       int ct=0;
-       int i;
-       STACK_OF(SRTP_PROTECTION_PROFILE) *clnt=0;
-       SRTP_PROTECTION_PROFILE *prof;
-    
-       clnt=SSL_get_srtp_profiles(s);    
-       ct=sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */
-
-       if(p)
-               {
-               if(ct==0)
-                       {
-                       SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST);
-                       return 1;
-                       }
-
-               if((2 + ct*2 + 1) > maxlen)
-                       {
-                       SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
-                       return 1;
-                       }
-
-                /* Add the length */
-                s2n(ct * 2, p);
-               for(i=0;i<ct;i++)
-                       {
-                       prof=sk_SRTP_PROTECTION_PROFILE_value(clnt,i);
-                       s2n(prof->id,p);
-                       }
-
-                /* Add an empty use_mki value */
-                *p++ = 0;
-               }
-
-       *len=2 + ct*2 + 1;
-    
-       return 0;
-       }
-
-
-int ssl_parse_clienthello_use_srtp_ext(SSL *s, unsigned char *d, int len,int *al)
-       {
-       SRTP_PROTECTION_PROFILE *cprof,*sprof;
-       STACK_OF(SRTP_PROTECTION_PROFILE) *clnt=0,*srvr;
-        int ct;
-        int mki_len;
-       int i,j;
-       int id;
-       int ret;
-
-         /* Length value + the MKI length */
-        if(len < 3)
-               {            
-               SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-                }
-
-        /* Pull off the length of the cipher suite list */
-        n2s(d, ct);
+{
+    return s->srtp_profile;
+}
+
+/*
+ * Note: this function returns 0 length if there are no profiles specified
+ */
+int ssl_add_clienthello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
+                                     int maxlen)
+{
+    int ct = 0;
+    int i;
+    STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = 0;
+    SRTP_PROTECTION_PROFILE *prof;
+
+    clnt = SSL_get_srtp_profiles(s);
+    ct = sk_SRTP_PROTECTION_PROFILE_num(clnt); /* -1 if clnt == 0 */
+
+    if (p) {
+        if (ct == 0) {
+            SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
+                   SSL_R_EMPTY_SRTP_PROTECTION_PROFILE_LIST);
+            return 1;
+        }
+
+        if ((2 + ct * 2 + 1) > maxlen) {
+            SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_USE_SRTP_EXT,
+                   SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
+            return 1;
+        }
+
+        /* Add the length */
+        s2n(ct * 2, p);
+        for (i = 0; i < ct; i++) {
+            prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
+            s2n(prof->id, p);
+        }
+
+        /* Add an empty use_mki value */
+        *p++ = 0;
+    }
+
+    *len = 2 + ct * 2 + 1;
+
+    return 0;
+}
+
+int ssl_parse_clienthello_use_srtp_ext(SSL *s, unsigned char *d, int len,
+                                       int *al)
+{
+    SRTP_PROTECTION_PROFILE *sprof;
+    STACK_OF(SRTP_PROTECTION_PROFILE) *srvr;
+    int ct;
+    int mki_len;
+    int i, srtp_pref;
+    unsigned int id;
+
+    /* Length value + the MKI length */
+    if (len < 3) {
+        SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    /* Pull off the length of the cipher suite list */
+    n2s(d, ct);
+    len -= 2;
+
+    /* Check that it is even */
+    if (ct % 2) {
+        SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    /* Check that lengths are consistent */
+    if (len < (ct + 1)) {
+        SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    srvr = SSL_get_srtp_profiles(s);
+    s->srtp_profile = NULL;
+    /* Search all profiles for a match initially */
+    srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr);
+
+    while (ct) {
+        n2s(d, id);
+        ct -= 2;
         len -= 2;
-        
-        /* Check that it is even */
-       if(ct%2)
-               {
-               SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-        
-        /* Check that lengths are consistent */
-       if(len < (ct + 1)) 
-               {
-               SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-
-        
-       clnt=sk_SRTP_PROTECTION_PROFILE_new_null();
-
-       while(ct)
-               {
-               n2s(d,id);
-               ct-=2;
-                len-=2;
-
-               if(!find_profile_by_num(id,&cprof))
-                       {
-                       sk_SRTP_PROTECTION_PROFILE_push(clnt,cprof);
-                       }
-               else
-                       {
-                       ; /* Ignore */
-                       }
-               }
-
-        /* Now extract the MKI value as a sanity check, but discard it for now */
-        mki_len = *d;
-        d++; len--;
-
-        if (mki_len != len)
-               {
-               SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_MKI_VALUE);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-
-       srvr=SSL_get_srtp_profiles(s);
-
-       /* Pick our most preferred profile. If no profiles have been
-        configured then the outer loop doesn't run 
-        (sk_SRTP_PROTECTION_PROFILE_num() = -1)
-        and so we just return without doing anything */
-       for(i=0;i<sk_SRTP_PROTECTION_PROFILE_num(srvr);i++)
-               {
-               sprof=sk_SRTP_PROTECTION_PROFILE_value(srvr,i);
-
-               for(j=0;j<sk_SRTP_PROTECTION_PROFILE_num(clnt);j++)
-                       {
-                       cprof=sk_SRTP_PROTECTION_PROFILE_value(clnt,j);
-            
-                       if(cprof->id==sprof->id)
-                               {
-                               s->srtp_profile=sprof;
-                               *al=0;
-                               ret=0;
-                               goto done;
-                               }
-                       }
-               }
-
-       ret=0;
-    
-done:
-       if(clnt) sk_SRTP_PROTECTION_PROFILE_free(clnt);
-
-       return ret;
-       }
-
-int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len, int maxlen)
-       {
-       if(p)
-               {
-               if(maxlen < 5)
-                       {
-                       SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
-                       return 1;
-                       }
-
-               if(s->srtp_profile==0)
-                       {
-                       SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,SSL_R_USE_SRTP_NOT_NEGOTIATED);
-                       return 1;
-                       }
-                s2n(2, p);
-               s2n(s->srtp_profile->id,p);
-                *p++ = 0;
-               }
-       *len=5;
-    
-       return 0;
-       }
-    
-
-int ssl_parse_serverhello_use_srtp_ext(SSL *s, unsigned char *d, int len,int *al)
-       {
-       unsigned id;
-       int i;
-        int ct;
-
-       STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
-       SRTP_PROTECTION_PROFILE *prof;
-
-       if(len!=5)
-               {
-               SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-
-        n2s(d, ct);
-       if(ct!=2)
-               {
-               SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-
-       n2s(d,id);
-        if (*d)  /* Must be no MKI, since we never offer one */
-               {
-               SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_MKI_VALUE);
-               *al=SSL_AD_ILLEGAL_PARAMETER;
-               return 1;
-               }
-
-       clnt=SSL_get_srtp_profiles(s);
-
-       /* Throw an error if the server gave us an unsolicited extension */
-       if (clnt == NULL)
-               {
-               SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,SSL_R_NO_SRTP_PROFILES);
-               *al=SSL_AD_DECODE_ERROR;
-               return 1;
-               }
-    
-       /* Check to see if the server gave us something we support
-          (and presumably offered)
-       */
-       for(i=0;i<sk_SRTP_PROTECTION_PROFILE_num(clnt);i++)
-               {
-               prof=sk_SRTP_PROTECTION_PROFILE_value(clnt,i);
-           
-               if(prof->id == id)
-                       {
-                       s->srtp_profile=prof;
-                       *al=0;
-                       return 0;
-                       }
-               }
-
-       SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
-       *al=SSL_AD_DECODE_ERROR;
-       return 1;
-       }
 
+        /*
+         * Only look for match in profiles of higher preference than
+         * current match.
+         * If no profiles have been have been configured then this
+         * does nothing.
+         */
+        for (i = 0; i < srtp_pref; i++) {
+            sprof = sk_SRTP_PROTECTION_PROFILE_value(srvr, i);
+            if (sprof->id == id) {
+                s->srtp_profile = sprof;
+                srtp_pref = i;
+                break;
+            }
+        }
+    }
+
+    /*
+     * Now extract the MKI value as a sanity check, but discard it for now
+     */
+    mki_len = *d;
+    d++;
+    len--;
+
+    if (mki_len != len) {
+        SSLerr(SSL_F_SSL_PARSE_CLIENTHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_MKI_VALUE);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    return 0;
+}
+
+int ssl_add_serverhello_use_srtp_ext(SSL *s, unsigned char *p, int *len,
+                                     int maxlen)
+{
+    if (p) {
+        if (maxlen < 5) {
+            SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
+                   SSL_R_SRTP_PROTECTION_PROFILE_LIST_TOO_LONG);
+            return 1;
+        }
+
+        if (s->srtp_profile == 0) {
+            SSLerr(SSL_F_SSL_ADD_SERVERHELLO_USE_SRTP_EXT,
+                   SSL_R_USE_SRTP_NOT_NEGOTIATED);
+            return 1;
+        }
+        s2n(2, p);
+        s2n(s->srtp_profile->id, p);
+        *p++ = 0;
+    }
+    *len = 5;
+
+    return 0;
+}
+
+int ssl_parse_serverhello_use_srtp_ext(SSL *s, unsigned char *d, int len,
+                                       int *al)
+{
+    unsigned id;
+    int i;
+    int ct;
+
+    STACK_OF(SRTP_PROTECTION_PROFILE) *clnt;
+    SRTP_PROTECTION_PROFILE *prof;
+
+    if (len != 5) {
+        SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    n2s(d, ct);
+    if (ct != 2) {
+        SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    n2s(d, id);
+    if (*d) {                   /* Must be no MKI, since we never offer one */
+        SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
+               SSL_R_BAD_SRTP_MKI_VALUE);
+        *al = SSL_AD_ILLEGAL_PARAMETER;
+        return 1;
+    }
+
+    clnt = SSL_get_srtp_profiles(s);
+
+    /* Throw an error if the server gave us an unsolicited extension */
+    if (clnt == NULL) {
+        SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
+               SSL_R_NO_SRTP_PROFILES);
+        *al = SSL_AD_DECODE_ERROR;
+        return 1;
+    }
+
+    /*
+     * Check to see if the server gave us something we support (and
+     * presumably offered)
+     */
+    for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) {
+        prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i);
+
+        if (prof->id == id) {
+            s->srtp_profile = prof;
+            *al = 0;
+            return 0;
+        }
+    }
+
+    SSLerr(SSL_F_SSL_PARSE_SERVERHELLO_USE_SRTP_EXT,
+           SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST);
+    *al = SSL_AD_DECODE_ERROR;
+    return 1;
+}
 
 #endif