The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=8d5c7813061dfa0b187500dfe3aeea7a28181c13
commit 8d5c7813061dfa0b187500dfe3aeea7a28181c13 Author: Mark Johnston <[email protected]> AuthorDate: 2021-05-25 17:59:09 +0000 Commit: Mark Johnston <[email protected]> CommitDate: 2021-05-26 20:30:23 +0000 libradius: Fix input validation bugs Approved by: so Security: FreeBSD-SA-21:12.libradius Security: CVE-2021-29629 MFC after: now Sponsored by: The FreeBSD Foundation --- lib/libradius/radlib.c | 54 ++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 39 insertions(+), 15 deletions(-) diff --git a/lib/libradius/radlib.c b/lib/libradius/radlib.c index e01c486a1ba6..18aee8b53024 100644 --- a/lib/libradius/radlib.c +++ b/lib/libradius/radlib.c @@ -187,7 +187,7 @@ is_valid_response(struct rad_handle *h, int srv, MD5_CTX ctx; unsigned char md5[MD5_DIGEST_LENGTH]; const struct rad_server *srvp; - int len; + int alen, len; #ifdef WITH_SSL HMAC_CTX *hctx; u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE]; @@ -206,8 +206,8 @@ is_valid_response(struct rad_handle *h, int srv, /* Check the message length */ if (h->in_len < POS_ATTRS) return 0; - len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1]; - if (len > h->in_len) + len = (h->in[POS_LENGTH] << 8) | h->in[POS_LENGTH + 1]; + if (len < POS_ATTRS || len > h->in_len) return 0; /* Check the response authenticator */ @@ -233,9 +233,16 @@ is_valid_response(struct rad_handle *h, int srv, /* Search and verify the Message-Authenticator */ hctx = HMAC_CTX_new(); while (pos < len - 2) { - if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) { - /* zero fill the Message-Authenticator */ + if (h->in[pos + 1] != MD5_DIGEST_LENGTH + 2) { + HMAC_CTX_free(hctx); + return 0; + } + if (len - pos < MD5_DIGEST_LENGTH + 2) { + HMAC_CTX_free(hctx); + return 0; + } + memset(&resp[pos + 2], 0, MD5_DIGEST_LENGTH); HMAC_Init_ex(hctx, srvp->secret, @@ -255,7 +262,12 @@ is_valid_response(struct rad_handle *h, int srv, } break; } - pos += h->in[pos + 1]; + alen = h->in[pos + 1]; + if (alen < 2) { + HMAC_CTX_free(hctx); + return 0; + } + pos += alen; } HMAC_CTX_free(hctx); } @@ -272,7 +284,7 @@ is_valid_request(struct rad_handle *h) MD5_CTX ctx; unsigned char md5[MD5_DIGEST_LENGTH]; const struct rad_server *srvp; - int len; + int alen, len; #ifdef WITH_SSL HMAC_CTX *hctx; u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE]; @@ -285,8 +297,8 @@ is_valid_request(struct rad_handle *h) /* Check the message length */ if (h->in_len < POS_ATTRS) return (0); - len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1]; - if (len > h->in_len) + len = (h->in[POS_LENGTH] << 8) | h->in[POS_LENGTH + 1]; + if (len < POS_ATTRS || len > h->in_len) return (0); if (h->in[POS_CODE] != RAD_ACCESS_REQUEST) { @@ -307,7 +319,18 @@ is_valid_request(struct rad_handle *h) pos = POS_ATTRS; hctx = HMAC_CTX_new(); while (pos < len - 2) { + alen = h->in[pos + 1]; + if (alen < 2) + return (0); if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) { + if (len - pos < MD5_DIGEST_LENGTH + 2) { + HMAC_CTX_free(hctx); + return (0); + } + if (alen < MD5_DIGEST_LENGTH + 2) { + HMAC_CTX_free(hctx); + return (0); + } memcpy(resp, h->in, MSGSIZE); /* zero fill the Request-Authenticator */ if (h->in[POS_CODE] != RAD_ACCESS_REQUEST) @@ -327,7 +350,7 @@ is_valid_request(struct rad_handle *h) } break; } - pos += h->in[pos + 1]; + pos += alen; } HMAC_CTX_free(hctx); #endif @@ -929,9 +952,9 @@ rad_cvt_string(const void *data, size_t len) * returns -1. */ int -rad_get_attr(struct rad_handle *h, const void **value, size_t *len) +rad_get_attr(struct rad_handle *h, const void **value, size_t *lenp) { - int type; + int len, type; if (h->in_pos >= h->in_len) return 0; @@ -940,13 +963,14 @@ rad_get_attr(struct rad_handle *h, const void **value, size_t *len) return -1; } type = h->in[h->in_pos++]; - *len = h->in[h->in_pos++] - 2; - if (h->in_pos + (int)*len > h->in_len) { + len = h->in[h->in_pos++]; + if (len < 2 || h->in_pos + len > h->in_len) { generr(h, "Malformed attribute in response"); return -1; } + *lenp = len; *value = &h->in[h->in_pos]; - h->in_pos += *len; + h->in_pos += len; return type; } _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/dev-commits-src-all To unsubscribe, send any mail to "[email protected]"
