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mirror of https://git.tartarus.org/simon/putty.git synced 2025-04-15 01:58:05 -05:00

Idiot me! store_host_key() was blindly _appending_ new host keys to

the end of the host key file. This is perfectly all right if a host
key never changes, but it's completely useless if you need to
replace an existing entry. This version should do better.

[originally from svn r3719]
This commit is contained in:
Simon Tatham 2004-01-17 13:00:18 +00:00
parent 2817a7e150
commit 276c8335af

View File

@ -19,7 +19,7 @@
#include "tree234.h"
enum {
INDEX_DIR, INDEX_HOSTKEYS, INDEX_RANDSEED,
INDEX_DIR, INDEX_HOSTKEYS, INDEX_HOSTKEYS_TMP, INDEX_RANDSEED,
INDEX_SESSIONDIR, INDEX_SESSION,
};
@ -98,6 +98,7 @@ static void make_filename(char *filename, int index, const char *subname)
index == INDEX_DIR ? "/.putty" :
index == INDEX_SESSIONDIR ? "/.putty/sessions" :
index == INDEX_HOSTKEYS ? "/.putty/sshhostkeys" :
index == INDEX_HOSTKEYS_TMP ? "/.putty/sshhostkeys.tmp" :
index == INDEX_RANDSEED ? "/.putty/randomseed" :
"/.putty/ERROR", FILENAME_MAX - len);
}
@ -495,26 +496,48 @@ int verify_host_key(const char *hostname, int port,
void store_host_key(const char *hostname, int port,
const char *keytype, const char *key)
{
FILE *fp;
int fd;
char filename[FILENAME_MAX];
FILE *rfp, *wfp;
char *newtext, *line;
int headerlen;
char filename[FILENAME_MAX], tmpfilename[FILENAME_MAX];
newtext = dupprintf("%s@%d:%s %s\n", keytype, port, hostname, key);
headerlen = 1 + strcspn(newtext, " "); /* count the space too */
/*
* Open both the old file and a new file.
*/
make_filename(filename, INDEX_HOSTKEYS, NULL);
fd = open(filename, O_CREAT | O_APPEND | O_RDWR, 0600);
if (fd < 0) {
char dir[FILENAME_MAX];
rfp = fopen(filename, "r");
if (!rfp)
return;
make_filename(tmpfilename, INDEX_HOSTKEYS_TMP, NULL);
wfp = fopen(tmpfilename, "w");
if (!wfp) {
fclose(rfp);
return;
}
make_filename(dir, INDEX_DIR, NULL);
mkdir(dir, 0700);
fd = open(filename, O_CREAT | O_APPEND | O_RDWR, 0600);
/*
* Copy all lines from the old file to the new one that _don't_
* involve the same host key identifier as the one we're adding.
*/
while ( (line = fgetline(rfp)) ) {
if (strncmp(line, newtext, headerlen))
fputs(line, wfp);
}
if (fd < 0) {
perror(filename);
exit(1);
}
fp = fdopen(fd, "a");
fprintf(fp, "%s@%d:%s %s\n", keytype, port, hostname, key);
fclose(fp);
/*
* Now add the new line at the end.
*/
fputs(newtext, wfp);
fclose(rfp);
fclose(wfp);
rename(tmpfilename, filename);
sfree(newtext);
}
void read_random_seed(noise_consumer_t consumer)