diff options
author | Gerald Combs <gerald@wireshark.org> | 2010-12-29 20:09:27 +0000 |
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committer | Gerald Combs <gerald@wireshark.org> | 2010-12-29 20:09:27 +0000 |
commit | cf6df46095526617b7738af219d4865c5a871f46 (patch) | |
tree | 2afb94d5fba3effdaf7a3e3980fd44655a24455d /asn1 | |
parent | 06a370929b61f0ddaba9b8bf94979b5c4be4a4e9 (diff) |
Fix a buffer overflow in the engineId preferences. Fixes bug 5530.
svn path=/trunk/; revision=35298
Diffstat (limited to 'asn1')
-rw-r--r-- | asn1/snmp/packet-snmp-template.c | 26 |
1 files changed, 15 insertions, 11 deletions
diff --git a/asn1/snmp/packet-snmp-template.c b/asn1/snmp/packet-snmp-template.c index 0a5971c983..3c3250dba2 100644 --- a/asn1/snmp/packet-snmp-template.c +++ b/asn1/snmp/packet-snmp-template.c @@ -1814,8 +1814,8 @@ snmp_usm_password_to_key_md5(const guint8 *password, guint passwordlen, /*****************************************************/ /* Now localize the key with the engineID and pass */ /* through MD5 to produce final key */ - /* May want to ensure that engineLength <= 32, */ - /* otherwise need to use a buffer larger than 64 */ + /* We ignore invalid engineLengths here. More strict */ + /* checking is done in snmp_users_update_cb. */ /*****************************************************/ md5_init(&MD); @@ -1840,7 +1840,7 @@ snmp_usm_password_to_key_sha1(const guint8 *password, guint passwordlen, guint8 *key) { sha1_context SH; - guint8 *cp, password_buf[72]; + guint8 *cp, password_buf[64]; guint32 password_index = 0; guint32 count = 0, i; @@ -1866,15 +1866,14 @@ snmp_usm_password_to_key_sha1(const guint8 *password, guint passwordlen, /*****************************************************/ /* Now localize the key with the engineID and pass */ /* through SHA to produce final key */ - /* May want to ensure that engineLength <= 32, */ - /* otherwise need to use a buffer larger than 72 */ + /* We ignore invalid engineLengths here. More strict */ + /* checking is done in snmp_users_update_cb. */ /*****************************************************/ - memcpy(password_buf, key, 20); - memcpy(password_buf+20, engineID, engineLength); - memcpy(password_buf+20+engineLength, key, 20); sha1_starts(&SH); - sha1_update(&SH, password_buf, 40+engineLength); + sha1_update(&SH, key, 20); + sha1_update(&SH, engineID, engineLength); + sha1_update(&SH, key, 20); sha1_finish(&SH, key); return; } @@ -1951,6 +1950,11 @@ snmp_users_update_cb(void* p _U_, const char** err) for (i=0; i<num_ueas-1; i++) { snmp_ue_assoc_t* u = &(ueas[i]); + /* RFC 3411 section 5 */ + if (u->engine.len < 5 || u->engine.len > 32) { + g_string_append_printf(es, "Invalid engineId length (%u). Must be between 5 and 32 (10 and 64 hex digits)\n", u->engine.len); + } + if ( u->user.userName.len == ue->user.userName.len && u->engine.len == ue->engine.len ) { @@ -1958,13 +1962,13 @@ snmp_users_update_cb(void* p _U_, const char** err) if (u->engine.len > 0 && memcmp( u->engine.data, ue->engine.data, u->engine.len ) == 0) { if ( memcmp( u->user.userName.data, ue->user.userName.data, ue->user.userName.len ) == 0 ) { /* XXX: make a string for the engineId */ - g_string_append_printf(es,"duplicate key (userName='%s')\n",ue->user.userName.data); + g_string_append_printf(es,"Duplicate key (userName='%s')\n",ue->user.userName.data); } } if (u->engine.len == 0) { if ( memcmp( u->user.userName.data, ue->user.userName.data, ue->user.userName.len ) == 0 ) { - g_string_append_printf(es,"duplicate key (userName='%s' engineId=NONE)\n",ue->user.userName.data); + g_string_append_printf(es,"Duplicate key (userName='%s' engineId=NONE)\n",ue->user.userName.data); } } } |