Hl add dhcp dissection #4
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
shla2022
reviewed
Sep 13, 2022
shla2022
reviewed
Sep 13, 2022
shla2022
reviewed
Sep 13, 2022
shla2022
reviewed
Sep 13, 2022
|
A few minor comments, generally looks good. |
|
@hl33ta should this target |
shla2022
reviewed
Sep 27, 2022
src/lib/protocols/dhcp.c
Outdated
Comment on lines
189
to
217
| } else if(id == 15 /* Domain Name */) { | ||
| char *name = (char*)&dhcp->options[i+2]; | ||
| int j = 0; | ||
|
|
||
| j = ndpi_min(len, sizeof(flow->protos.dhcp.domain_name)-1); | ||
| strncpy((char*)flow->protos.dhcp.domain_name, name, j); | ||
| flow->protos.dhcp.domain_name[j] = '\0'; | ||
| } else if(id == 50) /* Requested IP */ { | ||
| if (len > sizeof(flow->protos.dhcp.requested_ip)) | ||
| memcpy(&flow->protos.dhcp.requested_ip, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.requested_ip)); | ||
| else | ||
| memcpy(&flow->protos.dhcp.requested_ip, (char*)&dhcp->options[i+2], len); | ||
| } else if(id == 51) /* Lease Time */ { | ||
| if (len > sizeof(flow->protos.dhcp.lease_time)) | ||
| memcpy(&flow->protos.dhcp.lease_time, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.lease_time)); | ||
| else | ||
| memcpy(&flow->protos.dhcp.lease_time, (char*)&dhcp->options[i+2], len); | ||
| } else if(id == 54) /* Server Identifier */ { | ||
| if (len > sizeof(flow->protos.dhcp.server_ident)) | ||
| memcpy(&flow->protos.dhcp.server_ident, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.server_ident)); | ||
| else | ||
| memcpy(&flow->protos.dhcp.server_ident, (char*)&dhcp->options[i+2], len); | ||
| } else if(id == 58) /* Renewal Time */ { | ||
| if (len > sizeof(flow->protos.dhcp.renew_time)) | ||
| memcpy(&flow->protos.dhcp.renew_time, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.renew_time)); | ||
| else | ||
| memcpy(&flow->protos.dhcp.renew_time, (char*)&dhcp->options[i+2], len); | ||
| } | ||
|
|
There was a problem hiding this comment.
Consider the below approach as it includes less code. It should be easier to maintain and less prone to error.
Suggested change
| } else if(id == 15 /* Domain Name */) { | |
| char *name = (char*)&dhcp->options[i+2]; | |
| int j = 0; | |
| j = ndpi_min(len, sizeof(flow->protos.dhcp.domain_name)-1); | |
| strncpy((char*)flow->protos.dhcp.domain_name, name, j); | |
| flow->protos.dhcp.domain_name[j] = '\0'; | |
| } else if(id == 50) /* Requested IP */ { | |
| if (len > sizeof(flow->protos.dhcp.requested_ip)) | |
| memcpy(&flow->protos.dhcp.requested_ip, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.requested_ip)); | |
| else | |
| memcpy(&flow->protos.dhcp.requested_ip, (char*)&dhcp->options[i+2], len); | |
| } else if(id == 51) /* Lease Time */ { | |
| if (len > sizeof(flow->protos.dhcp.lease_time)) | |
| memcpy(&flow->protos.dhcp.lease_time, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.lease_time)); | |
| else | |
| memcpy(&flow->protos.dhcp.lease_time, (char*)&dhcp->options[i+2], len); | |
| } else if(id == 54) /* Server Identifier */ { | |
| if (len > sizeof(flow->protos.dhcp.server_ident)) | |
| memcpy(&flow->protos.dhcp.server_ident, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.server_ident)); | |
| else | |
| memcpy(&flow->protos.dhcp.server_ident, (char*)&dhcp->options[i+2], len); | |
| } else if(id == 58) /* Renewal Time */ { | |
| if (len > sizeof(flow->protos.dhcp.renew_time)) | |
| memcpy(&flow->protos.dhcp.renew_time, (char*)&dhcp->options[i+2], sizeof(flow->protos.dhcp.renew_time)); | |
| else | |
| memcpy(&flow->protos.dhcp.renew_time, (char*)&dhcp->options[i+2], len); | |
| } | |
| } else if(id == 15 /* Domain Name */) { | |
| char *name = (char*)&dhcp->options[i+2]; | |
| int j = 0; | |
| j = ndpi_min(len, sizeof(flow->protos.dhcp.domain_name)-1); | |
| strncpy((char*)flow->protos.dhcp.domain_name, name, j); | |
| flow->protos.dhcp.domain_name[j] = '\0'; | |
| } else if(id == 50) /* Requested IP */ { | |
| memcpy(&flow->protos.dhcp.requested_ip, (char*)&dhcp->options[i+2], ndpi_min(sizeof(flow->protos.dhcp.requested_ip), len)); | |
| } else if(id == 51) /* Lease Time */ { | |
| memcpy(&flow->protos.dhcp.lease_time, (char*)&dhcp->options[i+2], ndpi_min(sizeof(flow->protos.dhcp.lease_time),len)); | |
| } else if(id == 54) /* Server Identifier */ { | |
| memcpy(&flow->protos.dhcp.server_ident, (char*)&dhcp->options[i+2], ndpi_min(sizeof(flow->protos.dhcp.server_ident), len)); | |
| } else if(id == 58) /* Renewal Time */ { | |
| memcpy(&flow->protos.dhcp.renew_time, (char*)&dhcp->options[i+2], ndpi_min(sizeof(flow->protos.dhcp.renew_time), len)); | |
| } | |
|
A final comment intended to improve readability and ease future maintenance. Otherwise LGTM. |
shla2022
reviewed
Sep 29, 2022
src/lib/protocols/dhcp.c
Outdated
| @@ -114,6 +113,7 @@ void ndpi_search_dhcp_udp(struct ndpi_detection_module_struct *ndpi_struct, | |||
|
|
|||
| if(msg_type <= 8) { | |||
| foundValidMsgType = 1; | |||
| flow->protos.dhcp.valid = 1; | |||
There was a problem hiding this comment.
does this conflict with use of this field as a flag below?
There was a problem hiding this comment.
technically no it does the same thing as something like this would do flow->protos.dhcp.valid |= 0x01 would do because it happens before the other assignments. but i think replacing the above with flow->protos.dhcp.valid |= 0x01 makes the most sense. good point.
There was a problem hiding this comment.
Do we need to consider this in #6 as well ?
shla2022
approved these changes
Sep 29, 2022
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
adding additional dhcp info to export from ndpi