--- dropbear-2017.75.orig/svr-authpubkey.c 2017-05-18 16:47:02.000000000 +0200 +++ dropbear-2017.75/svr-authpubkey.c 2017-07-06 19:45:36.765143131 +0200 @@ -220,24 +220,33 @@ static int checkpubkey(char* algo, unsig goto out; } - /* we don't need to check pw and pw_dir for validity, since - * its been done in checkpubkeyperms. */ - len = strlen(ses.authstate.pw_dir); - /* allocate max required pathname storage, - * = path + "/.ssh/authorized_keys" + '\0' = pathlen + 22 */ - filename = m_malloc(len + 22); - snprintf(filename, len + 22, "%s/.ssh/authorized_keys", - ses.authstate.pw_dir); + /* special case for root authorized_keys in /etc/dropbear/authorized_keys */ + if (ses.authstate.pw_uid != 0) { - /* open the file as the authenticating user. */ - origuid = getuid(); - origgid = getgid(); - if ((setegid(ses.authstate.pw_gid)) < 0 || - (seteuid(ses.authstate.pw_uid)) < 0) { - dropbear_exit("Failed to set euid"); - } + /* we don't need to check pw and pw_dir for validity, since + * its been done in checkpubkeyperms. */ + len = strlen(ses.authstate.pw_dir); + /* allocate max required pathname storage, + * = path + "/.ssh/authorized_keys" + '\0' = pathlen + 22 */ + filename = m_malloc(len + 22); + snprintf(filename, len + 22, "%s/.ssh/authorized_keys", + ses.authstate.pw_dir); - authfile = fopen(filename, "r"); + /* open the file as the authenticating user. */ + origuid = getuid(); + origgid = getgid(); + if ((setegid(ses.authstate.pw_gid)) < 0 || + (seteuid(ses.authstate.pw_uid)) < 0) { + dropbear_exit("Failed to set euid"); + } + + authfile = fopen(filename, "r"); + + } else { + origuid = getuid(); + origgid = getgid(); + authfile = fopen("/etc/dropbear/authorized_keys","r"); + } if ((seteuid(origuid)) < 0 || (setegid(origgid)) < 0) { @@ -396,26 +405,39 @@ static int checkpubkeyperms() { goto out; } - /* allocate max required pathname storage, - * = path + "/.ssh/authorized_keys" + '\0' = pathlen + 22 */ - filename = m_malloc(len + 22); - strncpy(filename, ses.authstate.pw_dir, len+1); + if (ses.authstate.pw_uid != 0) { - /* check ~ */ - if (checkfileperm(filename) != DROPBEAR_SUCCESS) { - goto out; - } + /* allocate max required pathname storage, + * = path + "/.ssh/authorized_keys" + '\0' = pathlen + 22 */ + filename = m_malloc(len + 22); + strncpy(filename, ses.authstate.pw_dir, len+1); - /* check ~/.ssh */ - strncat(filename, "/.ssh", 5); /* strlen("/.ssh") == 5 */ - if (checkfileperm(filename) != DROPBEAR_SUCCESS) { - goto out; - } + /* check ~ */ + if (checkfileperm(filename) != DROPBEAR_SUCCESS) { + goto out; + } + + /* check ~/.ssh */ + strncat(filename, "/.ssh", 5); /* strlen("/.ssh") == 5 */ + if (checkfileperm(filename) != DROPBEAR_SUCCESS) { + goto out; + } + + /* now check ~/.ssh/authorized_keys */ + strncat(filename, "/authorized_keys", 16); + if (checkfileperm(filename) != DROPBEAR_SUCCESS) { + goto out; + } + + } else { + + if (checkfileperm("/etc/dropbear") != DROPBEAR_SUCCESS) { + goto out; + } + if (checkfileperm("/etc/dropbear/authorized_keys") != DROPBEAR_SUCCESS) { + goto out; + } - /* now check ~/.ssh/authorized_keys */ - strncat(filename, "/authorized_keys", 16); - if (checkfileperm(filename) != DROPBEAR_SUCCESS) { - goto out; } /* file looks ok, return success */